The test scores of 300 students are distributed normally with a mean of
78 and a standard deviation of 8. Find the number of students with scores between 71% and 87%.

Can someone explain the steps to this question as well? It'll be a great help!

Out of $20$ creepy-crawly creatures in a room, $80\%$ are flies and $20\%$ are spiders. if $s\%$ of the total legs belong to spiders, what is $s$?

What is the inverse of f(x) = 6x -24

Assume that adults have iq scores that are normally distributed with a mean of mu equals 100 and a standard deviation sigma equals 20. find the probability that a randomly selected adult has an iq between 80 and 120.assume that adults have iq scores that are normally distributed with a mean of mu equals 100 and a standard deviation sigma equals 20. find the probability that a randomly selected adult has an iq between 80 and 120.