Question

a man sells an article at a profit of 20%. if he bought it at 20% less and sold it for 75rs less, he would have gained 25%. what is the cost price ?

Answer 1

Let the C.P = 100 Rs.
Profit = 20% 
S.P = C.P*(100+P)/100 = 100*120/100 = 120 Rs.
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Had he bought it at 20% less:
C.P = 100 - 20% of 100 = 100-20 = 80 Rs.
Profit to be made after reducing the Selling Price = 25%
Hence, if the C.P was '80', 
S.P would be =  C.P*(100+P)/100 = 80*125/100 = 100 Rs.
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Now, for our assumed C.P (100 Rs.),
The difference in S.P = 120 - 100 = 20
ATQ, the difference in S.P should be 75
20 diff.=== 100(C.P)
75 diff.==== X (C.P)
20* X = 100*75
X = 375 Rs.
Hence C.P = Rs.375
Hope it helps.