Posted by amir on .
The numerator of a fractionis 5 less than twice the denominator. If the numerator is decreased by 1 and the denominator is increased by 3, the value of the new fraction is 5/4. Find the original fraction.

math 
Reiny,
old denominator  D
old numerator  2D5
new denomintor D1
new denom. 2D5 + 3
so (D1)/(2D2) = 5/4
solve 
OOPS again math 
Reiny,
I seem to be making some silly copying errors tonight
change to :
new denomintor D+3
new numerator 2D5  1
so (2D6)/(D+3) = 5/4
solve 
OOPS again math 
amir,
Oh now I get it. in the last step
3D=39

3 3
so D=13
tysm!
your a genius. 
math 
amir,
This is my work:
D1 5
=  Cross multiply you get:
2D2 4 10D10=4D4
4D 4D
6D10=4
+10+10
6D=6

6 6
D=1? 
math 
jing,
THE DENOMINATOR IS 4 MORE THAN ITS NUMERATOR.IT IS DECREASED FROM NUMERATOR AND 2 IS ADDED TO THE DENOMINATOR,THE RESULTING FRACTION IS 3/4.FIND THE ORIGINAL FRACTION.