Q: Milton has some books about zoology and 4 times as many books about botany. If he has 80 books total, how many zoology books does he have?
A: Let z be the number of zoology books and b be the number of botany books. We know that z + b = 80 and b = 4z. Substituting the second equation into the first equation, we get z + 4z = 80. Combining like terms, we get 5z = 80. Dividing both sides by 5, we get z = 16. The answer is 16.

Q: The school has 14 boys and 10 girls. If 4 boys and 3 girls drop out, how many boys and girls are left?
A: There are 14 boys - 4 boys = 10 boys left. There are 10 girls - 3 girls = 7 girls left. In total there are 10 boys + 7 girls = 17 boys and girls left. The answer is 17.

Q: Emily just purchased 2 pairs of curtains for $30.00 each and 9 wall prints at $15.00 each. The store also offers an installation service. For $50.00 they will come to your house and professionally hang your curtains and prints. If Emily agrees to this service, how much will her entire order cost?
A:
She buys 2 pair of curtains for $30.00 each so that's 2 * 30 = $60.00. She buys 9 wall prints at $15.00 each so that's 9 * 15 = $135.00. The curtains cost $60.00, the prints are $135.00 and the installation service is $50.00 for a total of 60 + 135 + 50 = $245.00. The answer is 245.