The denominator of a rational number is greater than its numerator by 3. If 3 is subtracted from the numerator and 2
The denominator of a rational number is greater than its numerator by 3. If 3 is subtracted from the numerator and 2 is added to the denominator the new number becomes 1/5. Then the original number was ……………
A) 7/11
B) 3/5
C) 5/8
D) 4/7
2 Answers
Correct option is (C) 5/8
Let the original rational number is \(\frac xy.\)
According to first condition, we have
y = x + 3 ___________(1)
According to second condition, we have
\(\frac{x-3}{y+2}=\frac15\)
\(\Rightarrow\) 5x - 15 = y + 2 (By cross multiplication)
\(\Rightarrow\) 5x - 15 = (x + 3) + 2 (From (1))
\(\Rightarrow\) 5x - x = 15 + 5
\(\Rightarrow\) 4x = 20
\(\Rightarrow\) x = \(\frac{20}4\) = 5
\(\therefore\) y = 5+3 = 8 (From (1))
\(\therefore\) Original number \(=\frac xy=\frac58.\)