If y : 196 : : 196 : 784, then what is the value of y?

Correct option is D

Given:

The proportion is:

y : 196 = 196 : 784

Formula Used:

In a proportion, the cross-products are equal, so we can write the equation:

​$$y \times 784 = 196 \times 196$$​​

Solution:

​$$196 \times 196 = 38416$$​​

So the equation becomes:

​$$y \times 784 = 38416 \\y = \frac{38416}{784} = 49$$​​