Question

Ronan has some pen and pencil which together are in 70 in number if he give 5 pencil to his youngster brother and 5 pen to his youngster sister then the number of pen would become double the number of pen find the number of pen and pencil Ronan has

Answer 1

Let the no of pens=x
Let the no of pencil=y

x+y=70 ---

x-5+y-5=2x
x+y-10=2x
-x+y=10
x-y=-10 ---

x+y=70
x-y=-10
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2x=60
x=30.
PENS=30
PENCIL=70-30=40