Question

x,15,12,9 are in proportion. find the value of x​

Answer 1

Answer:

The value of x would be 18

see the ques carefully that there is add of 3 in the series of these numbers as:-

9+3=12

12+3=15

similarly

15+3=18

Answer 2

Answer:

20

Step-by-step explanation:

if a : b = c : d are in proportion then a/b = c/d

i.e. ad = bc

Product of extremes = Product of means

This is called cross product rule

x : 15 : 12 : 9

⇒ 9x = 15 × 12

⇒ 9x = 180

⇒ x = 180 ÷ 9 = 20

So 'x' = 20