Answer the following question.
Liza bought 10 kilograms of butter to make cookies. She used one-half of it for chocolate chip cookies, one-fifth of it for peanut butter cookies, and one-third of the remaining butter for sugar cookies. How many kilograms of butter are left after making those three kinds of cookies?
Step-by-step reasoning process: Liza used 10 / 2 = 5 kilograms of butter for the chocolate chip cookies. Then, she used 10 / 5 = 2 kilograms of butter for the peanut butter cookies. She used 5 + 2 = 7 kilograms of butter for the chocolate and peanut butter cookies. So, only 10 - 7 = 3 kilograms of butter was left. Then, Liza used 3 / 3 = 1 kilograms of butter for the sugar cookies. Therefore, only 3 - 1 = 2 kilograms of butter were left.
The answer is 2.

Answer the following question.
There are 180 students in ninth grade. 1/4 of them bombed their finals because they were going through difficult breakups. 1/3rd of the rest didn't show up to take the test, and another 20 got less than a D. How many students passed their finals?
Step-by-step reasoning process: First find the number of students who went through breakups: 1 / 4 * 180 = 45 students. Then subtract that number from the total number: 180 students - 45 students = 135 students. Then divide that number by 3 to find the number of students who didn't show up to take the test: 135 students / 3 = 45 students. Then subtract the number of students who failed in each way from the total number to find the number who passed: 180 students - 45 students - 45 students - 20 students = 70 students.
The answer is 70.

Answer the following question.
Mike is 16 years old. His sister Barbara is half as old as he is. How old is Barbara going to be when Mike is 24 years old?
Step-by-step reasoning process: Barbara is currently 16 years / 2 = 8 years old. Mike is going to be 24 years old after 24 years - 16 years = 8 years. So Barbara is going to be 8 years + 8 years = 16 years old.
The answer is 16.

Answer the following question.
Grace started her own landscaping business. She charges $6 an hour for mowing lawns, $11 for pulling weeds and $9 for putting down mulch. In September she mowed lawns for 63 hours, pulled weeds for 9 hours and put down mulch for 10 hours. How much money did she earn in September?
Step-by-step reasoning process: Grace mowed lawns for 63 hours at $6 / hour, so earned 63 * 6 = $378. Grace pulled weeds for 9 hours at $11 / hour, so earned 9 * 11 = $99. Grace put down mulch for 10 hours at $9 / hour, so earned 10 * 9 = $90. During September Grace earned $378 + $99 + $90 = $567.
The answer is 567.