Math Flash Cards for 4th Graders to Flip and Print
Seven fourth grade skills, one fact to a card, with the working on the back.
All 135 cards
Times facts 6 to 12 24
6 × 6 36: 5 × 6 = 30 and 1 × 6 = 6, and 30 + 6 = 36. 6 × 7 42: 5 × 7 = 35 and 1 × 7 = 7, and 35 + 7 = 42. 6 × 8 48: 5 × 8 = 40 and 1 × 8 = 8, and 40 + 8 = 48. 6 × 9 54: 5 × 9 = 45 and 1 × 9 = 9, and 45 + 9 = 54. 6 × 11 66: 6 × 10 = 60 and 6 × 1 = 6, and 60 + 6 = 66. 6 × 12 72: 6 × 10 = 60 and 6 × 2 = 12, and 60 + 12 = 72. 7 × 7 49: 5 × 7 = 35 and 2 × 7 = 14, and 35 + 14 = 49. 7 × 8 56: 5 × 8 = 40 and 2 × 8 = 16, and 40 + 16 = 56. 7 × 9 63: 5 × 9 = 45 and 2 × 9 = 18, and 45 + 18 = 63. 7 × 11 77: 7 × 10 = 70 and 7 × 1 = 7, and 70 + 7 = 77. 7 × 12 84: 7 × 10 = 70 and 7 × 2 = 14, and 70 + 14 = 84. 8 × 8 64: 5 × 8 = 40 and 3 × 8 = 24, and 40 + 24 = 64. 8 × 9 72: 5 × 9 = 45 and 3 × 9 = 27, and 45 + 27 = 72. 8 × 11 88: 8 × 10 = 80 and 8 × 1 = 8, and 80 + 8 = 88.
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Times facts 6 to 12
Prime or composite
Rounding
Equal fractions
Tenths and hundredths
Unit changes
Area and perimeter
Times facts 6 to 12, continued
8 × 12 96: 8 × 10 = 80 and 8 × 2 = 16, and 80 + 16 = 96. 9 × 9 81: 5 × 9 = 45 and 4 × 9 = 36, and 45 + 36 = 81. 9 × 11 99: 9 × 10 = 90 and 9 × 1 = 9, and 90 + 9 = 99. 9 × 12 108: 9 × 10 = 90 and 9 × 2 = 18, and 90 + 18 = 108. 10 × 10 100: ten tens make one hundred. 10 × 11 110: 11 tens. 10 × 12 120: 12 tens. 11 × 11 121: 11 × 10 = 110 and 11 × 1 = 11, and 110 + 11 = 121. 11 × 12 132: 11 × 10 = 110 and 11 × 2 = 22, and 110 + 22 = 132. 12 × 12 144: 12 × 10 = 120 and 12 × 2 = 24, and 120 + 24 = 144.
Prime or composite 21
Prime or composite? 2 prime: the only factors of 2 are 1 and 2. It is the only even prime. Prime or composite? 9 composite: 9 = 3 × 3, so it has more than two factors. Prime or composite? 13 prime: the only factors of 13 are 1 and 13. Prime or composite? 15 composite: 15 = 3 × 5, so it has more than two factors. Prime or composite? 21 composite: 21 = 3 × 7, so it has more than two factors. Prime or composite? 23 prime: the only factors of 23 are 1 and 23. Prime or composite? 27 composite: 27 = 3 × 9, so it has more than two factors. Prime or composite? 29 prime: the only factors of 29 are 1 and 29. Prime or composite? 37 prime: the only factors of 37 are 1 and 37. Prime or composite? 39 composite: 39 = 3 × 13, so it has more than two factors. Prime or composite? 41 prime: the only factors of 41 are 1 and 41. Prime or composite? 49 composite: 49 = 7 × 7, so it has more than two factors. Prime or composite? 51 composite: 51 = 3 × 17, so it has more than two factors. Prime or composite? 53 prime: the only factors of 53 are 1 and 53. Prime or composite? 57 composite: 57 = 3 × 19, so it has more than two factors. Prime or composite? 67 prime: the only factors of 67 are 1 and 67. Prime or composite? 79 prime: the only factors of 79 are 1 and 79. Prime or composite? 87 composite: 87 = 3 × 29, so it has more than two factors. Prime or composite? 91 composite: 91 = 7 × 13, so it has more than two factors. Prime or composite? 97 prime: the only factors of 97 are 1 and 97. Prime, composite or neither? 1 neither: 1 has one factor, itself. A prime has exactly two.
Rounding 18
Round to nearest 10: 34 30: the ones digit is 4, so round down. Round to nearest 10: 47 50: the ones digit is 7, so round up. Round to nearest 10: 65 70: the ones digit is 5, so round up. Round to nearest 10: 152 150: the ones digit is 2, so round down. Round to nearest 10: 348 350: the ones digit is 8, so round up. Round to nearest 10: 995 1,000: the ones digit is 5, so round up. Round to nearest 100: 249 200: the tens digit is 4, so round down. Round to nearest 100: 351 400: the tens digit is 5, so round up. Round to nearest 100: 650 700: the tens digit is 5, so round up. Round to nearest 100: 1,449 1,400: the tens digit is 4, so round down. Round to nearest 100: 2,960 3,000: the tens digit is 6, so round up. Round to nearest 100: 8,075 8,100: the tens digit is 7, so round up. Round to nearest 1,000: 2,499 2,000: the hundreds digit is 4, so round down. Round to nearest 1,000: 4,678 5,000: the hundreds digit is 6, so round up. Round to nearest 1,000: 6,500 7,000: the hundreds digit is 5, so round up. Round to nearest 1,000: 9,964 10,000: the hundreds digit is 9, so round up. Round to nearest 1,000: 12,350 12,000: the hundreds digit is 3, so round down. Round to nearest 1,000: 27,810 28,000: the hundreds digit is 8, so round up.
Equal fractions 18
1/2 = 3/? 6: 1/2 = 3/6. To get there, multiply top and bottom by 3. 1/2 = ?/8 4: 1/2 = 4/8. To get there, multiply top and bottom by 4. 1/2 = ?/10 5: 1/2 = 5/10. To get there, multiply top and bottom by 5. 1/2 = ?/100 50: 1/2 = 50/100. To get there, multiply top and bottom by 50. 1/3 = 4/? 12: 1/3 = 4/12. To get there, multiply top and bottom by 4. 1/3 = ?/6 2: 1/3 = 2/6. To get there, multiply top and bottom by 2. 1/4 = ?/8 2: 1/4 = 2/8. To get there, multiply top and bottom by 2. 2/3 = ?/12 8: 2/3 = 8/12. To get there, multiply top and bottom by 4. 2/5 = ?/10 4: 2/5 = 4/10. To get there, multiply top and bottom by 2. 3/4 = ?/12 9: 3/4 = 9/12. To get there, multiply top and bottom by 3. 3/4 = ?/100 75: 3/4 = 75/100. To get there, multiply top and bottom by 25. 3/5 = ?/100 60: 3/5 = 60/100. To get there, multiply top and bottom by 20. 4/6 = ?/3 2: 4/6 = 2/3. To get there, divide top and bottom by 2. 5/10 = ?/2 1: 5/10 = 1/2. To get there, divide top and bottom by 5. 6/8 = ?/4 3: 6/8 = 3/4. To get there, divide top and bottom by 2. 8/10 = ?/5 4: 8/10 = 4/5. To get there, divide top and bottom by 2. 9/12 = ?/4 3: 9/12 = 3/4. To get there, divide top and bottom by 3. 10/12 = ?/6 5: 10/12 = 5/6. To get there, divide top and bottom by 2.
Tenths and hundredths 18
0.08 = ?/100 8: 0.08 is 8 hundredths, which is 8/100. 0.4 = ?/10 4: 0.4 is 4 tenths, which is 4/10. 0.5 = ?/100 50: 0.5 is 50 hundredths, which is 50/100. 0.62 = ?/100 62: 0.62 is 62 hundredths, which is 62/100. 1 3/10 as a decimal 1.3: 1 whole and 3 tenths. 1/10 as a decimal 0.1: 1 tenth. The digit sits in the tenths place. 2 45/100 as a decimal 2.45: 2 whole and 45 hundredths. 3/10 = ?/100 30: each tenth is 10 hundredths, so 3 tenths are 30 hundredths. 3/10 as a decimal 0.3: 3 tenths. The digit sits in the tenths place. 5/100 as a decimal 0.05: 5 hundredths, so a 0 holds the tenths place. 7/10 as a decimal 0.7: 7 tenths. The digit sits in the tenths place. 7/100 as a decimal 0.07: 7 hundredths, so a 0 holds the tenths place. 25/100 as a decimal 0.25: 25 hundredths is 2 tenths and 5 hundredths. 43/100 as a decimal 0.43: 43 hundredths is 4 tenths and 3 hundredths. 60/100 as a decimal 0.6: 60 hundredths is 6 tenths, so 0.60 and 0.6 are equal. 70/100 = ?/10 7: 10 hundredths make 1 tenth, so 70 hundredths are 7 tenths. Which is greater? 0.09 or 0.1 0.1: it is 10 hundredths, and 0.09 is only 9 hundredths. Which is greater? 0.3 or 0.25 0.3: it is 30 hundredths, and 0.25 is only 25 hundredths.
Unit changes 18
2 feet = ? inches 24: 1 foot is 12 inches, and 2 × 12 = 24. 2 hours = ? minutes 120: 1 hour is 60 minutes, and 2 × 60 = 120. 2 kilograms = ? grams 2,000: 1 kilogram is 1,000 grams, and 2 × 1,000 = 2,000. 2 meters = ? centimeters 200: 1 meter is 100 centimeters, and 2 × 100 = 200. 2 minutes = ? seconds 120: 1 minute is 60 seconds, and 2 × 60 = 120. 2 pounds = ? ounces 32: 1 pound is 16 ounces, and 2 × 16 = 32. 3 feet = ? inches 36: 1 foot is 12 inches, and 3 × 12 = 36. 3 hours = ? minutes 180: 1 hour is 60 minutes, and 3 × 60 = 180. 3 liters = ? milliliters 3,000: 1 liter is 1,000 milliliters, and 3 × 1,000 = 3,000. 3 pounds = ? ounces 48: 1 pound is 16 ounces, and 3 × 16 = 48. 4 kilometers = ? meters 4,000: 1 kilometer is 1,000 meters, and 4 × 1,000 = 4,000. 5 feet = ? inches 60: 1 foot is 12 inches, and 5 × 12 = 60. 5 kilograms = ? grams 5,000: 1 kilogram is 1,000 grams, and 5 × 1,000 = 5,000. 5 minutes = ? seconds 300: 1 minute is 60 seconds, and 5 × 60 = 300. 6 meters = ? centimeters 600: 1 meter is 100 centimeters, and 6 × 100 = 600. 7 kilometers = ? meters 7,000: 1 kilometer is 1,000 meters, and 7 × 1,000 = 7,000. 8 liters = ? milliliters 8,000: 1 liter is 1,000 milliliters, and 8 × 1,000 = 8,000. 9 meters = ? centimeters 900: 1 meter is 100 centimeters, and 9 × 100 = 900.
Area and perimeter 18
Area: 5 by 5 square 25 square units: area is length × width, 5 × 5 = 25. Area: 6 by 4 rectangle 24 square units: area is length × width, 6 × 4 = 24. Area: 7 by 3 rectangle 21 square units: area is length × width, 7 × 3 = 21. Area: 8 by 5 rectangle 40 square units: area is length × width, 8 × 5 = 40. Area: 9 by 2 rectangle 18 square units: area is length × width, 9 × 2 = 18. Area: 10 by 6 rectangle 60 square units: area is length × width, 10 × 6 = 60. Area: 11 by 4 rectangle 44 square units: area is length × width, 11 × 4 = 44. Area: 12 by 5 rectangle 60 square units: area is length × width, 12 × 5 = 60. Area: 20 by 3 rectangle 60 square units: area is length × width, 20 × 3 = 60. Perimeter: 5 by 5 square 20 units: add all four sides, 5 + 5 + 5 + 5 = 20. Perimeter: 6 by 4 rectangle 20 units: add all four sides, 6 + 4 + 6 + 4 = 20. Perimeter: 7 by 3 rectangle 20 units: add all four sides, 7 + 3 + 7 + 3 = 20. Perimeter: 8 by 5 rectangle 26 units: add all four sides, 8 + 5 + 8 + 5 = 26. Perimeter: 9 by 2 rectangle 22 units: add all four sides, 9 + 2 + 9 + 2 = 22. Perimeter: 10 by 6 rectangle 32 units: add all four sides, 10 + 6 + 10 + 6 = 32. Perimeter: 11 by 4 rectangle 30 units: add all four sides, 11 + 4 + 11 + 4 = 30. Perimeter: 12 by 5 rectangle 34 units: add all four sides, 12 + 5 + 12 + 5 = 34. Perimeter: 20 by 3 rectangle 46 units: add all four sides, 20 + 3 + 20 + 3 = 46.
How this list was compiled: Own work. Every answer and every line of working is computed with whole-number and fraction arithmetic; the finished deck was then read back and each answer worked out again (checked 2026-09-30). A prime has exactly two factors, a composite number more, and 1 is neither: https://en.wikipedia.org/wiki/Prime_number and https://en.wikipedia.org/wiki/Composite_number . The unit facts (12 inches in a foot, 16 ounces in a pound, 60 minutes in an hour and 60 seconds in a minute, kilo for a thousand, centi for a hundredth, milli for a thousandth): https://en.wikipedia.org/wiki/United_States_customary_units , https://en.wikipedia.org/wiki/Pound_%28mass%29 , https://en.wikipedia.org/wiki/Minute , https://en.wikipedia.org/wiki/Metric_prefix and https://en.wikipedia.org/wiki/Centimetre . Six of the seven sets follow skills the Common Core State Standards for Mathematics list for grade 4 (primes and composites to 100, rounding, equal fractions, decimals for tenths and hundredths, unit sizes, and the area and perimeter of rectangles), read in the copy at https://learning.ccsso.org/wp-content/uploads/2022/11/ADA-Compliant-Math-Standards.pdf . The times facts are the grade 3 facts carried on to 12 × 12. The choice of grade is this site's reading, not an alignment. Licence: own work
How it works Math flash cards for 4th graders in seven sets: times facts from 6 to 12, prime or composite, rounding, equal fractions, tenths and hundredths, unit changes, and area and perimeter. Every back shows the answer with its working.
Read the full guide
Seven sets, one skill each
The deck opens on the times facts with both factors from 6 to 12. Turn one card, then pick another set under Show only, or open More options to type your answers. A rounding back names the digit that decides, and a fraction back says what to multiply or divide by.
Print one set at a time
Pick a set, turn a card and press the print button under the card: twelve cards fill a sheet of Letter or A4. Print double-sided, flipped on the long edge, and 56 lands behind 7 × 8.
When you type an answer, start a decimal with a zero: 0.7, not .7.
Area counts the squares inside a rectangle. Perimeter is the distance around it.
Questions and answers
What math should a 4th grader know?
The Common Core lists these for grade 4, among others: primes and composites to 100, rounding, equal fractions, decimals for tenths and hundredths, unit changes, and the area and perimeter of rectangles. The times facts are grade 3 facts. Our reading, not an alignment.
Is 1 a prime number?
No. A prime number has exactly two factors, 1 and itself. The number 1 has only one factor, so it is neither prime nor composite.
How do you round to the nearest hundred?
Look at the tens digit. If it is 5 or more, round up; if it is 4 or less, round down. So 351 rounds up to 400 and 249 rounds down to 200.
How do you write tenths and hundredths as decimals?
Read them straight off: 7/10 is 0.7 and 43/100 is 0.43. With fewer than ten hundredths, a zero holds the tenths place, so 5/100 is 0.05.