Question

On selling coffee at Rs.135 per kg a loss of 10% is incurred. Calculate the amount of coffee sold, if the total loss incurred is Rs.180.

Answer 1

S.P. of 1 kg of coffee = Rs.135
Loss % = 10%
Now, 
`"S.P."/"C.P." = 1 - "Loss"/(100)`

⇒ `(135)/"C.P." = 1 - (10)/(100)`

⇒ `(135)/"C.P." = (100 - 10)/(100)`

⇒ C.P. = `(100)/(90) xx 135`
= Rs.150
∴ C.P. of 1 kg of coffee = Rs.150
∴ Loss per 1kg of coffee
= C.P. - S.P.
= Rs.150 - Rs.135
= Rs.15
Total loss incurred = Rs.180
∴ Amount of coffee sold
= `"Total loss"/"loss per 1 kg of  coffee"`
= `(180)/(15)`
= 12kg.