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

What number must be added to each of the numbers 10, 18, 22, 38 to get the numbers which are in proportion ?

What number must be subtracted from each of the numbers 10, 12, 19, 24 to get the numbers which are in proportion ?

What must be added to each of the four numbers 6, 9, 12, and 17 such that the new numbers are in proportion?

What must be added to each of the numbers 3, 7, 8 and 16 so that resulting numbers are in proportion ?

What number should be added to each of the number 6,7,15,17 so that the resulting numbers are in proportion ?

What should be added to each of the numbers 8, 32,and 1,11 so that the new numbers are in proportion?

What number should be added to each of the four numbers 4. I, 26, and 12 so that the new numbers are in proportion?