If 7(x) + 5, 7(x) + 4, 5(x) + 5 and y are in proportion when x = 5, find the value of y.

Correct option is D

Given:

7(x) + 5, 7(x) + 4, 5(x) + 5 and y are in proportions

Formula Used:

If the numbers a,b,c and d are in proportions then:

a:b::c:d

​$$a \times d = b \times c$$​​

Solution:

Hence the 7(x) + 5, 7(x) + 4, 5(x) + 5 and y are in proportion

Putting the value of x =5

7(5) + 5: 7(5) + 4:: 5(5) + 5 : y

40:39::30 : y

Hence y =$$\frac{39 \times 30}{40}$$​ = 29.25