Question

7:21=10:3z
find the value of x in this ratio
​

Answer 1

z=10

Explanation:

We know that the ratio 7:21 is equal to the ratio of 10:3z.

Let's model that in proportions:

7 10

- = -

21 3z

Now that the equation is in proportional form, we can cross-multiply to find the value of z.

7 * 3z = 21 * 10 - Multiply both sides

21z = 210 - Divide both sides by 21

z=10

The answer is z=10.