Question

what should be added to each of the numbers 12,30,40 and 86 so that they are in proportion?​

Answer 1

Answer:

6

Step-by-step explanation:

Suppose X should be added .

so the numbers in proportion are

(12+X), (30+X), (40+X) & (86+X)

As the numbers are in proportion

●(12+X) × (86+X) = (30+X) × (40+X)

●1032 + 12X + 86X + X^2 = 1200 + 30X+40X + X^2

●98X - 70X = 1200 - 1032

●28X=168

●X=168/28

● X=6