Question
Sarla had Rs. 8000 in total. She spent x% of this amount on
food. After that, she spent (x + 20)% of the remaining money on rent. Additionally, she spent Rs. 1920 on clubbing. The remaining amount, which she saved, is 31.25% of her initial amount. Based on this information, determine the value of x.Solution
Amount saved by Sarla = 0.3125 Γ 8000 = Rs. 2500
Amount spent on food = x/100 Γ 8000 = Rs. 80x
Amount spent on rent = (x + 20)/100 Γ (8000 β 80x) = (x + 20)(80 β 0.8x)
Or, 80x + (x + 20)(80 β 0.8x) = 8000 β 2500 β 1920 = 3580
Or, 80x + 80x + 1600 β 0.8x 2 Β β 16x = 3580
Or, 0.8x 2 Β β 144x + 1980 = 0
Or, x 2 Β β 180x + 2475 = 0
Or, x 2 Β β 165x β 15x + 2475 = 0
Or, x(x β 165) β 15(x β 165) = 0
Or, (x β 15)(x β 165) = 0
Or, x = 15 [x = 165 is not possible]
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