Question

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 ,,

Answer 1

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