Question

The numerator of a fraction is 2 less than the denominata When both
mumerator and denominator are increased by 3. the fraction is increased by
3/20. Original fraction is.
A
В. 32
C 53
D. 3/5
lon​

Answer 1

Answer:

D

Explanation:

first denominator -- x

first numerator ---- x-2

new denominator -- x+3

new numerator ---- x+1

(x-2)/x + 3/20 = (x+1)/(x+3)

times 20x(x+3) , the LCD

20(x+3)(x+1) + 3x(x+3) = 20x(x+1)

expanding and simplifying gave me

x^2 + 3x - 40 = 0

(x-5)(x+8) = 0

x = 5 or x=-8

if x=5, the original fraction was 3/5

if x=-8 the original fraction was -10/-8 or 5/4

check for 3/5 , new fraction would be 6/8 or 3/4

3/5 + 3/20 = 12/20 + 3/20 = 15/20 = 3/4

but for 5/4, new fraction would be 8/7

5/4 + 3/20 = 28/20 = 7/5 ≠ 8/7

BUT, if we take the unsimplified fraction -10/-8 , new fraction would be -7/-5 = 7/5