15 is you answer sir. the multiples are 15,30,45,60,75<span>,90,105,120,135,150,165,180,195,210,225,240,255,270,285,300,315</span>
Answer:

Step-by-step explanation:
let x be the numerator of the rational number then 2x is the denominator
original fraction = 
subtracting 3 from numerator and adding 7 to denominator , gives
=
( cross- multiply )
5(x - 3) = 2(2x + 7) ← distribute parenthesis on both sides )
5x - 15 = 4x + 14 ( subtract 4x from both sides )
x - 15 = 14 ( add 15 to both sides )
x = 29
rational number = 
A number into which each number in a given set may be evenly divided
2,4,6,8 and so on