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Question
10% of x + 20% of y = 24
3x - y = 20
Solution
10% of x + 20% of y = 24
⇒ 0.1x + 0.2y = 24 .....(1) [ On Simplyfying ]
3x - y = 20 .....(2)
Multiply equation (2) by 0.2, We get :
0.6x - 0.2y = 4 ......(3)
Adding equation (3) and (1)
0.6x - 0.2y = 4
+ 01x + 0.2y = 24
0.7x = 28
x = 40
Substituting x = 40 in equation (1), We get
0.1(40) + 0.2y = 24
⇒ 0.2y = 20
⇒ y = 100
∴ Solution is x = 40 and y = 100.
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