Answer:
$275
Step-by-step explanation:
Add 250+25 which equals 275
The correct way is to plug in the answer back into the equation and see if it results in the correct solution.
The sample space of the experiment (i.e. the total number of ways he can pick 7 random pages out of a total of 6 + 4 = 10 pages) is given by:

If he picks at least 5 pages of maths homework, this means that he either picked 5 pages or 6 pages of maths homework.
The number of ways he can pick 5 or 6 maths homework is given by:

Therefore, the probability that he recovers at least 5 pages of his math homework is given by: