Question

If 25,x,2 x,72 are in proportion then what is value of x

Answer 1

then
x/25 =72/2x,

x/25 =36/x,

so
x²=36×25,

x=√(36×25),

x=6×5,

x=30

Answer 2

Answer:

Given conditions are in proportion:

 $25:x :: 2x: 72$

To solve this proportion, we know that the first term and the fourth term of a proportion are called extreme terms or extremes,

and second term and the third term are called middle terms/

Therefore, in a proportion the product of extremes =product of middle terms.                         ......[1]

In the given condition:

first term = 25

Second term = x

third term = 2x

and fourth term = 72.

Then, the product of extremes = $25 \times 72 = 1800$

and the product of middle = $2x \times x = 2x^2$

[1] ⇒ $1800=2x^2$

Divide by 2 both sides of an equation:

$900 =x^2$  or

$x=\sqrt{900} = 30$

Therefore, the value of x is, 30