SOLUTION: shubhangi has twice as many 20 rupees notes.as she has 50 rupees notes. she has 2700 rupees .how many 50 rupees notes she have?

Algebra ->  Coordinate Systems and Linear Equations  -> Lessons -> SOLUTION: shubhangi has twice as many 20 rupees notes.as she has 50 rupees notes. she has 2700 rupees .how many 50 rupees notes she have?      Log On


   



Question 1095944: shubhangi has twice as many 20 rupees notes.as she has 50 rupees notes. she has 2700 rupees .how many 50 rupees notes she have?
Found 2 solutions by greenestamps, josgarithmetic:
Answer by greenestamps(13200) About Me  (Show Source):
You can put this solution on YOUR website!

Since she has twice as many 20r notes as 50r notes, think of grouping the notes into groups of one 50r note and two 20r notes. Then each group is 90 rupees.

Since she has a total of 2700 rupees, the number of these groups she has must be 2700/90 = 30.

So all together she has 30 50r notes and 60 20r notes.

Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
x, 20 rupee notes
y, 50 rupee notes
x%2Fy=2
x=2y
-
20x%2B50y=2700
2x%2B5y=270

-
simple substitution for x
2%282y%29%2B5y=270
9y=270
highlight%28y=30%29-------- 30 of the fifty rupee notes