A textbook store sold a combined total of 432 physics and biology textbooks in a week. The number of physics textbooks sold was two times the number of biology textbooks sold. How many textbooks of each type were sold?

At noon a tank contained 10cm water. after several hours it contained 7cm of water. what is the percent decrease of water in the tank?

Which shows one way to determine the facts of x3+4x2+5x+20 by grouping

Let us imagine that the number of automobile accidents in a certain region are related to the regional number of registered automobiles in tens of thousands (b1), alcoholic beverage sales in $10,000 (b2), and decrease in the price of gasoline in cents (b3). furthermore, imagine that the regression formula has been calculated as: y = a + b1x1 + b2x2 + b3x3 where y = the number of automobile accidents, a = 7.5, b1 = 3.5, b2 = 4.5, and b3 = 2.5 calculate the expected number of automobile accidents for a football weekend if the region has 25,000 registered vehicles, $75,000 worth of beer is sold, and a gas war causes a 10 cent drop in a gallon of gas.