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If 4 is addedto the numerator of a certain fraction,it becomes 7/10.If 4 is added to the denominator,it becomes1/2.Find the fraction?

Answer 1

Eva Adamson

Fraction is #17/30#

Let the fraction be #x/y#.

When #4# is added to numerator it becomes #(x+4)/y# and as it is #7/10#, we have

#(x+4)/y=7/10# or #10x+40=7y# i.e. #y=(10x+40)/7# .........(A)

and when #4# is added to denominator it becomes #x/(y+4)# and as it is #1/2#, we have

#x/(y+4)=1/2#or #2x=y+4#

Now putting value of #y# from (A), we get

#2x=(10x+40)/7+4#

or #14x=10x+40+28#

or #14x-10x=68#

or #4x=68# i.e, #x=68/4=17#

and #y=(10x+40)/7=(170+40)/7=210/7=30#

Hence, fraction is #17/30#

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Answer 2

Avery Alexander

The fraction is ( \frac{1}{2} ).

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.