Every spider has 8 compound eyes. How many eyes have 21 spiders?

A nail 4 inches long is driven through a board so that it projects 1.695 inches on one side and 1.428 on the other. How thick is the board?

Find the perimeter of an envelope 5 in. by 3¼ in.

How many minutes in 59 of 94 of an hour?

Mrs. Knox is 34 as old as Mr. Knox, who is 48 years old. Their son Edward is 49 as old as his mother. How old is Edward?

Suppose a pie to be exactly round and 10½ miles in diameter. If it were cut into 6 equal pieces, how long would the curved edge of each piece be?

813% of a class of 36 boys were absent on a rainy day. 3313% of those present went out of the room to the school yard. How many were left in the room?

Just after a ton of hay was weighed in market, a horse ate one pound of it. What was the ratio of what he ate to what was left?

If a fan having 15 rays opens out so that the outer rays form a straight line, how many degrees are there between any two adjacent rays?

One half of the distance between St. Louis and New Orleans is 280 miles more than 110 of the distance; what is the distance between these places?