a reduction of 20% in the price of sugar enables a purchaser to obtain 2.5 kg more for Rs.160.find the original rate and the reduced price per kg.

(a) 8.80 per kg
(b) 10.80 ,,
(c) 11.80 ,,
(d) 12.80 ,,

1 answer

original price ---- x
reduced price = .8x

number of kg purchased at original price = 160/x
number of kg purchased at reduced price = 160/(.8x)

160/(.8x) - 160/x = 2/5
200/x - 160/x = 2.5
40/x = 2.5
2.5x = 40
x = 16

find the original rate ????

the reduced price = .8(16) = 12.8, which is choice d)

check:
number of kg bought at original price = 160/16 = 10
number of kg bought at reduced price = 160/12.8 = 12.5
which is 2.5 kg more