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?
1 Answer
Jun 9, 2016
Explanation:
Suppose the original amount is
"Percent" means per-cent, i.e. per-hundred, so:
#10%# of#x# is#10/100 x = 0.1 x#
Having spent
#x - 0.1x = (1-0.1)x = 0.9x# rupees
Then:
#60%# of the remaining#0.9x# rupees is:
#60/100 0.9x=0.6*0.9x#
When subtracted from the
#0.9x - 0.6*0.9x = (1-0.6)*0.9x = 0.4*0.9x = 0.36x#
We are told that this is
#0.36x = 72#
Divide both sides by
#x = 72/0.36 = 200#