80 , decreased by three times a number , is the same as five times the number , increased by 8 . find the number

What is this inequality notation? t is less then or equal to 2

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.

X^2/100+y^2/25=1 the length of the major axis is: a)5 b)10 c)20