) Galvin bought as many non-fiction books as fiction books from a book fair.
He read 6 non-fiction books and 13 fiction books. He then had ? as many non-fiction
books left to read as fiction books. How many books did Galvin buy altogether?
4​

Which of the following is the result of expanding the series

You are standing next to a really big circular lake. you want to measure the diameter of the lake, but you don't want to have to swim across with a measuring tape! you decide to walk around the perimeter of the lake and measure its circumference, and find that it's 400\pi\text{ m}400? m. what is the diameter dd of the lake?

Bobs burgers bam has a special deal of 4 hamburgers for $6. at that rate, how much should it cost to buy 3 hamburgers?