Hence, to divide a fraction by a whole number, divide the numerator; or when that cannot be done, multiply the denominator by the divisor. α α 21. What is of ? of is and is twice as much, α b 36 Hence, to multiply one fraction by another, multiply the numerators together for a new numerator, and the denominators together for a new denominator. Arith. Art. XVII. We have seen that a fraction may be divided by multiplying its denominator, because the parts are made smaller; on the contrary, a fraction may be multiplied by dividing its denominator, because the parts are made larger. Arith. Art. XVIII. If the denominator be divided by 2, the unit is divided into only one half as many parts; consequently the parts must be twice as large as before. If the denominator be divided by 5, the unit is divided into only one fifth as many parts; hence the parts must be five times as large as before, and if the same number of parts be used as at first, the value of the fraction will be five times as great and so on. a If we divide the denominator by b, the fraction becomes 1 in which a is divided into part as many parts; hence the parts, and consequently the fraction is b times as large as 38. Multiply 3 |