Question

What number should be added to each of the numbers 3, 5, 13 and 19 so that the resulting numbers may be in proportion?

Answer 1

Answer:

if we add 2 to all these no. we can get the resulting no. in proportion

3+2=5

5+2=7

13+2=15

19+2=21

now,

5:7: :15:21

if you see , we get

5:7: :5:7

here 15 and 21 are multiple of 3