A man spends 10% of his rupees, then 60% of the remaining rupees. Given that he has Rs.72 left, how many rupees did he start with?

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tsjutten20 · Accepted Answer

Suppose the original amount is x rupees.   Percent means per-cent, i.e. per-hundred, so:  10% of x is 10100x=0.1x  Having spent 10% of x rupees he then has:  x−0.1x=(1−0.1)x=0.9x rupees  Then: 60% of the remaining 0.9x rupees is:  601000.9x=0.6⋅0.9x  When subtracted from the 0.9x rupees it leaves:  0.9x−0.6⋅0.9x=(1−0.6)⋅0.9x=0.4⋅0.9x=0.36x  We are told that this is Rs.72, so:  0.36x=72  Divide both sides by 0.36 to find:  x=720.36=200

Brynn Ortiz · Accepted Answer

Calculation:   100%−10%=90%   60% from 90%=54%   Total expense: 10%+54%=64%   Remaining 36% is 72.   Whole money involved:   10036×72=200

RizerMix · Accepted Answer

1x−(0.10x+0.60(90100)x=72 1x−0.10x+0.54x=72 0.36x=72 x=200 Check 10x=20(10%) 0.6×180(Remainder)=108 200−(20+108)=72

A man spends 10% of his rupees, then 60% of

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