Question

what number must be added to each of the numbers 5,9,7,12 to get the numbers which are in proportion​

Answer 1

Answer:

Let x be added to 5,9,17,27 to make them proportional

(5+x):(9+x)=(17+x):(27+x)

Product of mean=Product of extreme

(17+x)(9+x)=(5+x)(27+x)

153+17x+9x+x

2

=135+5x+27x+x

2

153+26x=135+32x

32x−26x=153−135

6x=18

x=3