The math teacher, Ms. Zentz, is buying appropriate math tools to use throughout the year. She is planning on buying twice as many rulers as protractors. The number of calculators Ms. Zentz is planning on buying is one quarter of the number of protractors. If Ms. Zentz buys 65 items, how many protractors does Ms. Zentz buy?

Answer:The correct answer is 20 protectors, 40 rulers, 5 calculators.Step-by-step explanation:The number that we need to calculate in first place is the protectors number it has to be a number that can get a quarter quantity with no decimals. so we calculate from 5 to 5 and get 20 protectors, we double that number and get the number of 40 rulers and the quarter of 20 is 5 so we have 5 calculators which in total is 65. In this kind of exercises is important to calculate the first number of the item that is going to be multiplied or divided, that first number is going to be obtained by calculating and doing the equations as many times as needed until we obtain the total number the problem is asking for.