Mariah has a spinner that has 10 equal sections, each containing a different number from 1 to 10. Mariah determines about how many times the spinner will land on a number that is greater than 7 in 250 spins, and her work is shown below.

P(number greater than 7)= Numbers greater than 7/ Total number of sections times number of spins = 4/10 (250) = 100

What mistake did Mariah make, if any?