Question

what number must be added to each of the numbers 5,9,7,12 to get the numbers which are in proportion?
please give me right answers.

Answer 1

Answer:

5.6 answer to the question

Answer 2

Answer:

3

Step-by-step explanation:

Let the added number be 'X'

So,

》 (5+X)/(9+X)=(7+X)/(12+X)

》 63+9X+7X+X² = 60+12X+5X+X²

》63+16X+X² = 60+17X+X²

》17X-16X+X²-X² = 63-60

》 X=3

Hence, the added number is 3.