Dena is biking down a 7/8 mile bike trail. she stops to greet a friend after biking 3/8 of a mile. how much farther does she need to travel?

Idon’t understand this.. will someone ? will mark brainliest along with 20 points.

(a) (8%) compute the probability of an even integer among the 100 integers 1! , 2! , 3! , until 100! (here n! is n factorial or n*(n-1)*(n-2) *… 1) (b) (16%) compute the probability of an even integer among the 100 integers: 1, 1+2, 1+2+3, 1+2+3+4, …., 1+2+3+… + 99, and 1+2+3+… + 100

Determine the number of girls in a math class with 87 boys if there are 25 girls for every 75 boys