If 60% of (x−y) = 45% (x+y) and y=k% of x, then 49% of k is equal to:

Given equation:
60% of (x−y)=45% of (x+y)
100
60
​
(x−y)=
100
45
​
(x+y)
60(x−y)=45(x+y)
Divide both sides by 15:

4(x−y)=3(x+y)
4x−4y=3x+3y
4x−3x=3y+4y
x=7y⟹y=
7
1
​
x
We are given y=k% of x:

y=
100
k
​
x
Comparing the two expressions for y:

100
k
​
=
7
1
​
⟹k=
7
100
​

Now, find 49% of k:

49% of k=
100
49
​
×
7
100
​
=7