Answer:
70%
Explanation:
First we calculate X using the following formula:
X = 25/100 * 104
X = 0.25 * 104
X = 26
Then we calculate Y using the following formula:
7 = 10/100 * Y
7 = 0.1 * Y
7/0.1 = Y
Y = 70
Then we calculate N as per the formula below:
N = 80/100 * Y
N = 0.8 * 70
N = 56
Finally using the formula mentioned in question we derive Y what percent of N + Y - X:
= Y/ (N + Y - X) * 100
= 70/ (56 + 70 - 26) * 100
= 70/100 * 100
= 70%