if one is added to the numerator of fraction, it becomes 1/5; if one is taken from the denominator, it becomes 1/7, find the fraction
Answers
Step-by-step explanation:
let the numerator be x and denominator be y
according to the first condition
(x + 1) / y = 1/5
5x + 5 = y
5x - y = -5 –––––1
according to he second condition
x/ (y - 1 ) = 1/7
7x = y - 1
7x - y = -1 –––––2
subtracting equation 2 from 1
7x -y = -1
5x - y = -5
2x = -6
x = -3
substituting x = -3 in equation 1
5x - y = -5
5(-3) - = -5
-15 - y = -5
-y = -5 + 15
-y = 10
y = -10
Answer:
2/15
Step-by-step explanation:
Let the fraction be x/y
Then according to the given conditions, we have
(x + 1)/y = 1/5
5 (x + 1) = y
5x + 5 = y
⇒ 5x – y = -5 … (i)
And,
x/(y – 1) = 1/7
7x = y – 1
7x – y = -1 … (ii)
Now, subtracting (i) from (ii) we get
7x – y = -1
5x – y = -5
(-)–(+)-(+)—
2x = 4
x = 2
On substituting the value of x in (i), we get
5(2) – y = -5
10 – y = -5
y = 10 + 5
y = 15
Therefore, the fraction is 2/15.