How do you solve #\frac { 35} { w } = \frac { 63} { 9}#?

1 Answer
Sep 6, 2017

See some solution processes below:

Explanation:

Process 1:

First, because both sides of the equation are single fractions we can "flip" the fractions giving:

#w/35 = 9/63#

Now, multiply each side of the equation by #color(red)(35)# to solve for #w# while keeping the equation balanced:

#color(red)(35) xx w/35 = color(red)(35) xx 9/63#

#cancel(color(red)(35)) xx w/color(red)(cancel(color(black)(35))) = color(red)(35) xx 9/(9 xx 7)#

#cancel(color(red)(35)) xx w/color(red)(cancel(color(black)(35))) = color(black)(cancel(color(red)(35)))color(red)(5) xx color(blue)(cancel(color(black)(9)))/(color(blue)(cancel(color(black)(9))) xx color(red)(cancel(color(black)(7))))#

#w = 5#

Process 2:

In this process we can first factor the term on the right side of the equation:

#35/w = 63/9#

#35/w = (9 xx 7)/9#

#35/w = (color(red)(cancel(color(black)(9))) xx 7)/color(red)(cancel(color(black)(9)))#

#35/w = 7#

Now, we can multiply each side of the equation by #color(red)(w)/color(blue)(7)# to solve for #w# while keeping the equation balanced:

#color(red)(w)/color(blue)(7) xx 35/w = color(red)(w)/color(blue)(7) xx 7#

#cancel(color(red)(w))/cancel(color(blue)(7)) xx (color(blue)(cancel(color(black)(35)))5)/color(red)(cancel(color(black)(w))) = color(red)(w)/cancel(color(blue)(7)) xx color(blue)(cancel(color(black)(7)))#

#5 = w#

#w = 5#

Process 3:

We can cross product or cross multiply the equation:

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#color(orange)(35)/color(orange)(w) = color(blue)(63)/color(blue)(9)#

#color(orange)(35) xx color(blue)(9) = color(blue)(63) xx color(orange)(w)#

#315 = 63w#

Now, divide each side of the equation by #color(red)(63)# to solve for #w# while keeping the equation balanced:

#(315)/color(red)(63) = (63w)/color(red)(63)#

#(63 xx 5)/color(red)(63) = (color(red)(cancel(color(black)(63)))w)/cancel(color(red)(63))#

#(color(red)(cancel(color(black)(63))) xx 5)/cancel(color(red)(63)) = w#

#5 = w#

#w = 5#