A textbook store sold a combined total of 478 biology and history textbooks in a week. The number of biology textbooks sold was 48 more than the number of number of history textbooks sold. how many textbooks of each type were sold

Monthly water bills for a city have a mean of $108.43 and a standard deviation of $32.09. find the probability that a randomly selected bill will have an amount greater than $155, which the city believes might indicate that someone is wasting water. would a bill that size be considered unusual?

Is the square root of 4 plus the square root of 16 rational?

The function f(x) = 14,600(1.1)* represents the population of a town x years after it was established. what was the original population of the town?