Answer this question:A family bought 1 box of pizza that is cut into 16 slices. Only three-fourths of the pizza was eaten by the family. How many slices of pizza were left?
The family ate 16 x 3 / 4 = 12 slices. So, there were 16 - 12 = 4 slices of pizza left.
The answer is 4.

Answer this question:Ludwig works 7 days a week and he usually works half of the day during Friday, Saturday, and Sunday. If his daily salary is $10, how much does he earn every week?
Ludwig earns a total of $10 x 4 = $40 from Monday to Thursday. He earns $10 / 2 = $5 per day on Friday, Saturday, and Sunday. So, his total salary for Friday, Saturday, Sunday is $5 x 3 = $15. Therefore, his total weekly salary is $40 + $15 = $55.
The answer is 55.

Answer this question:Marcos has to get across a 5 mile lake in his speedboat in 10 minutes so he can make it to work on time. How fast does he need to go in miles per hour to make it?
10 minutes for 5 miles means 10 minutes / 5 miles = 2 minutes / mile. 1 hour is 60 minutes so 60 minutes / hour / 2 minutes / mile = 30 miles / hour.
The answer is 30.

Answer this question:A library has a number of books. 35% of them are intended for children and 104 of them are for adults. How many books are in the library?
65% of the library books are for adults because 100 - 35 = 65. There are 160 library books in total because 104 / .65 = 160.
The answer is 160.