Q.8)Usha bought a certain number of chocolates at the
rate of 16 chocolates for `12 and the same number of
chocolates at the rate of 24 chocolates for `20. She sold
all of them at the rate of 30 chocolates for `30. Find her
gain / loss percentage

16 Chocolates for 12 and another 16 at rate of (24 chocolates for 20)

For buying 16 chocolates at this rate, cost incurred= 20/24×16= 40/3
Total CP= 16+40/3=76/3 for 32 chocolates

For 1 chocolate, CP= 76/3÷3=76/96=19/24

Profit=SP-CP=1-19/24=5/24
Profit percentage=5/24×100=20.83

16 chocolates for 12, another 16 for 13.33 (At the rate of 24 chocolates for 20)
Total cost = 12+13.33 = 25.33
Profit = 32 - 25.33 = 6.66
Profit %age= 6.66/25.33 x 100 = 26.31%