The denominator of a certain fraction exceeds twice the numerator by 4. If the numerator is increased by 14 and the denominator is decreased by 9, the value of the resulting fraction is the multiplicative inverse of 3/7 . What is the fraction.

פתרון

T h e d e n o mina t or o f a cer t ain f r a c t i o n e x cee d s tw i ce t h e n u m er a t or b y 4. I f t h e n u m er a t or i s in cre a se d b y 14 an d t h e d e n o mina t or i s d ecre a se d b y 9, t h e v a l u e o f t h e res u lt in g f r a c t i o n i s t h e m u lt i pl i c a t i v e in v erse o f \frac{3}{7} . Wha t i s t h e f r a c t i o n .

The number : \frac{113}{222}

צעדי פתרון

Represent the numbers with

x

numerator : x

denominator : 2 x + 4

A.T.Q.:

\frac{x + 14}{2 x + 4 - 9} = \frac{3}{7}

\frac{x + 14}{2 x + 4 - 9} = \frac{3}{7}, x

פתור בשביל:

x = - 113

\frac{x}{2 x + 4} = \frac{- 113}{2 ( - 113 ) + 4} = \frac{113}{222}

The number : \frac{113}{222}