Question

Fill in the missing number that makes the ratios equivalent.

4 : 3 = ____ : 21

Please help. :)

Answer 1

To determine the missing number in the ratios 4 : 3 = x : 21, we create and solve a proportion through cross multiplication. We find that the missing number is 28, making the equivalent ratios 4 : 3 = 28 : 21.

Step-by-step explanation:

To find the missing number that makes the ratios equivalent, we set up a proportion where the two ratios equal each other:

4 : 3 = x : 21

Next, we write the proportion as two fractions and set them equal to each other:

4/3 = x/21

Now we cross multiply to find the value of x:

4 * 21 = 3 * x

84 = 3x

To solve for x, we divide both sides of the equation by 3:

x = 84 / 3

x = 28

Therefore, the missing number that makes the ratios equivalent is 28, and the equivalent ratios are 4 : 3 = 28 : 21.