Ratios of two numbers

Practice working with ratios of two numbers. Find the missing number that makes each equality true.

These questions help you understand how the numbers in a ratio are related and how to find a missing value.

This practice helps you:

• understand ratios of numbers;
• find a missing number in a ratio;
• develop mental calculation skills;
• prepare for tests.

Read the explanation for each question carefully. To review ratios, study the lesson “Ratios of two numbers”.

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24$>>","buttons":["6","12","24"]},{"text":"$6 : 11 = 18 : \\ ?$","answer":0,"explanation":"$\\frac{18}{x} = \\frac{6}{11}$<br>$18 \\cdot 11 = x \\cdot 6$<br>$x = 33$","correct_text":"$6 : 11 = 18 : $<<$\\ 33>>$","buttons":["33","29","36"]},{"text":"$7 : 10 = 21 : \\ ?$","answer":1,"explanation":"$\\frac{21}{x} = \\frac{7}{10}$<br>$21 \\cdot 10 = x \\cdot 7$<br>$x = 30$","correct_text":"$7 : 10 = 21 : $<<$\\ 30$>>","buttons":["24","30","38"]},{"text":"$8 : 3 = 16 : \\ ?$","answer":2,"explanation":"$\\frac{16}{x} = \\frac{8}{3}$<br>$16 \\cdot 3 = x \\cdot 8$<br>$x = 6$","correct_text":"$8 : 3 = 16 : $<<$\\ 6$>>","buttons":["11","9","6"]},{"text":"$9 : 2 = 27 : \\ ?$","answer":0,"explanation":"$\\frac{27}{x} = \\frac{9}{2}$<br>$27 \\cdot 2 = x \\cdot 9$<br>$x = 6$","correct_text":"$9 : 2 = 27 : $<<$\\ 6$>>","buttons":["6","8","10"]},{"text":"$4 : 7 = 20 : \\ ?$","answer":1,"explanation":"$\\frac{20}{x} = \\frac{4}{7}$<br>$20 \\cdot 7 = x \\cdot 4$<br>$x = 35$","correct_text":"$4 : 7 = 20 : $<<$\\ 35$>>","buttons":["29","35","41"]},{"text":"$3 : 5 = 18 : \\ ?$","answer":0,"explanation":"$\\frac{18}{x} = \\frac{3}{5}$<br>$18 \\cdot 5 = x \\cdot 3$<br>$x = 30$","correct_text":"$3 : 5 = 18 : $<<$\\ 30$>>","buttons":["30","36","49"]},{"text":"$2 : 3 = 14 : \\ ?$","answer":2,"explanation":"$\\frac{14}{x} = \\frac{2}{3}$<br>$14 \\cdot 3 = x \\cdot 2$<br>$x = 21$","correct_text":"$2 : 3 = 14 :$ <<$\\ 21$>>","buttons":["28","17","21"]},{"text":"$3 : 5 = 21 : \\ ?$","answer":2,"explanation":"$\\frac{21}{x} = \\frac{3}{5}$<br>$21 \\cdot 5 = x \\cdot 3$<br>$x = 35$","correct_text":"$3 : 5 = 21 : $<<$\\ 35$>>","buttons":["27","32","35"]},{"text":"$4 : 7 = 16 : \\ ?$","answer":1,"explanation":"$\\frac{16}{x} = \\frac{4}{7}$<br>$16 \\cdot 7 = x \\cdot 4$<br>$x = 28$","correct_text":"$4 : 7 = 16 : $<<$\\ 28$>>","buttons":["21","28","32"]},{"text":"$5 : 6 = 20 : \\ ?$","answer":0,"explanation":"$\\frac{20}{x} = \\frac{5}{6}$<br>$20 \\cdot 6 = x \\cdot 5$<br>$x = 24$","correct_text":"$5 : 6 = 20 : $<<$\\ 24$>>","buttons":["24","26","28"]},{"text":"$7 : 8 = 28 : \\ ?$","answer":0,"explanation":"$\\frac{28}{x} = \\frac{7}{8}$<br>$28 \\cdot 8 = x \\cdot 7$<br>$x = 32$","correct_text":"$7 : 8 = 28 : $<<$\\ 32$>>","buttons":["32","38","45"]},{"text":"$6 : 11 = 24 : \\ ?$","answer":2,"explanation":"$\\frac{24}{x} = \\frac{6}{11}$<br>$24 \\cdot 11 = x \\cdot 6$<br>$x = 44$","correct_text":"$6 : 11 = 24 : $<<$\\ 44$>>","buttons":["30","35","44"]},{"text":"$9 : 10 = 36 : \\ ?$","answer":2,"explanation":"$\\frac{36}{x} = \\frac{9}{10}$<br>$36 \\cdot 10 = x \\cdot 9$<br>$x = 40$","correct_text":"$9 : 10 = 36 : $<<$\\ 40$>>","buttons":["38","39","40"]},{"text":"$8 : 9 = 32 : \\ ?$","answer":0,"explanation":"$\\frac{32}{x} = \\frac{8}{9}$<br>$32 \\cdot 9 = x \\cdot 8$<br>$x = 36$","correct_text":"$8 : 9 = 32 : $<<$\\ 36$>>","buttons":["36","38","40"]},{"text":"$10 : 7 = 40 : \\ ?$","answer":1,"explanation":"$\\frac{40}{x} = \\frac{10}{7}$<br>$40 \\cdot 7 = x \\cdot 10$<br>$x = 28$","correct_text":"$10 : 7 = 40 : $<<$\\ 28$>>","buttons":["26","28","31"]},{"text":"$3 : 4 = 18 : \\ ?$","answer":1,"explanation":"$\\frac{18}{x} = \\frac{3}{4}$<br>$18 \\cdot 4 = x \\cdot 3$<br>$x = 24$","correct_text":"$3 : 4 = 18 : $<<$\\ 24$>>","buttons":["22","24","26"]},{"text":"$2 : 7 = 10 : \\ ?$","answer":2,"explanation":"$\\frac{10}{x} = \\frac{2}{7}$<br>$10 \\cdot 7 = x \\cdot 2$<br>$x = 35$","correct_text":"$2 : 7 = 10 : $<<$\\ 35$>>","buttons":["30","33","35"]},{"text":"$3 : 8 = 9 : \\ ?$","answer":0,"explanation":"$\\frac{9}{x} = \\frac{3}{8}$<br>$9 \\cdot 8 = x \\cdot 3$<br>$x = 24$","correct_text":"$3 : 8 = 9 : $<<$\\ 24$>>","buttons":["24","26","29"]},{"text":"$4 : 5 = 28 : \\ ?$","answer":1,"explanation":"$\\frac{28}{x} = \\frac{4}{5}$<br>$28 \\cdot 5 = x \\cdot 4$<br>$x = 35$","correct_text":"$4 : 5 = 28 : $<<$\\ 35$>>","buttons":["34","35","36"]},{"text":"$6 : 7 = 30 : \\ ?$","answer":2,"explanation":"$\\frac{30}{x} = \\frac{6}{7}$<br>$30 \\cdot 7 = x \\cdot 6$<br>$x = 35$","correct_text":"$6 : 7 = 30 : $<<$\\ 35$>>","buttons":["31","33","35"]},{"text":"$5 : 9 = 25 : \\ ?$","answer":0,"explanation":"$\\frac{25}{x} = \\frac{5}{9}$<br>$25 \\cdot 9 = x \\cdot 5$<br>$x = 45$","correct_text":"$5 : 9 = 25 : $<<$\\ 45$>>","buttons":["45","50","55"]},{"text":"$7 : 4 = 21 : \\ ?$","answer":2,"explanation":"$\\frac{21}{x} = \\frac{7}{4}$<br>$21 \\cdot 4 = x \\cdot 7$<br>$x = 12$","correct_text":"$7 : 4 = 21 : $<<$\\ 12$>>","buttons":["8","10","12"]},{"text":"$8 : 11 = 32 : \\ ?$","answer":0,"explanation":"$\\frac{32}{x} = \\frac{8}{11}$<br>$32 \\cdot 11 = x \\cdot 8$<br>$x = 44$","correct_text":"$8 : 11 = 32 : $<<$\\ 44$>>","buttons":["44","49","54"]},{"text":"$9 : 5 = 27 : \\ ?$","answer":1,"correct_text":"$9 : 5 = 27 : $<<$\\ 15$>>","buttons":["12","15","18"]},{"text":"$10 : 3 = 50 : \\ ?$","answer":0,"explanation":"$\\frac{50}{x} = \\frac{10}{3}$<br>$50 \\cdot 3 = x \\cdot 10$<br>$x = 15$","correct_text":"$10 : 3 = 50 : $<<$\\ 15$>>","buttons":["15","30","45"]},{"text":"$4 : 3 = 20 : \\ ?$","answer":2,"explanation":"$\\frac{20}{x} = \\frac{4}{3}$<br>$20 \\cdot 3 = x \\cdot 4$<br>$x = 15$","correct_text":"$4 : 3 = 20 : $<<$\\ 15$>>","buttons":["5","10","15"]}]}