Answer:
5
Explanation:
Let's call the original number x.
So, the first student did x+23, and the other student did x-1.
You know that the first students result was 7 times larger than the other students. So, you can make the equation:
x+23=7(x-1)
x+23=7x-7
Then, do the algebra
-6x=-30
x=5