If the numerator and denominator contain common factors, remove them in accordance with Principle 6 stated above. This process is called cancellation.

If several fractions are to be multiplied together, the process is the

Observe that as all the factors (except the 1's) of the numerator are cancelled, the numerator of the answer is 1.

ORAL DRILL

In each of the following examples find the product of the numbers given:

Mixed Numbers. To multiply a fraction by a mixed

number, or to multiply one mixed number by another, observe the following rule.

Rule. (1) Express the mixed numbers as fractions,

In each of the following examples find the product of the

Rule.

Division of Fractions

To divide one fraction by another, invert the

divisor and proceed as in multiplication.

EXAMPLE 1. Divide by 18.

In each of the following examples divide the first number

4. What is of 49? 50 is of what number?

5. What fractions equal to 39, 48?

have for numerators 6, 51, 33,

6. If of a mine is worth $27,000, what is the entire mine worth?

7. If 3 yards of cloth are required to make a garment, how many such garments can be made from a piece containing 56 yards?

8. If a tractor-drawn reaper travels 33 miles per hour, how many more miles will it travel in a 12-hour day than a horsedrawn reaper that goes two miles per hour?

10. A boy being asked to find the value of 84 +27 +33 +4, gave as his answer 18. How great an error did he make?

11. Seven cars carried respectively 24, 183, 15, 28, 17, 32, 27 tons of coal. Required the number of tons carried. 12. Simplify 7 × 51 × 157 × 151.

13. Which is the greater, or 1, and how much?

14. A man owns a 4 interest in a ranch. If he sells of his share, what fraction of the whole will he still have? If the entire ranch is worth $300,000 what is the value of his holding?

15. A farmer had 480 bushels of corn. He put of it into one bin and the rest into another. He sold of what was in the first bin and of what was in the other. The rest he kept. How much did he keep?

16. If a motor-boat goes 65.017 miles per hour, what is the time required to travel one mile?

17. How many minutes will it take a pipe supplying water at the rate of 25 gallons per minute to fill a tank holding 70 gallons?

18. Express 15 as a fraction whose denominator is 320.