Question

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

Answer 1

hey here is your answer.
Let the number to be added be x
The no 5,9,17,27 will be
5+x,9+x,17+x,27+x
therefore 5+x divided by 9 +x = 17+x divided by 27 +x
(5+x(27+x)= (17+x)
153+9x+17x+x'2=135+5x+127x+x'2
153+26x+x'2=135+32x+ x'2
Minus X'2 from both sides. so the proportion is 3
hope it may help you.