Question

13. The selling price of 18 books is equal to the cost price of 21 books. Find the gain or loss per cent.
14. The cost price of 12 fans is equal to the selling price of 16 fans. Find the gain or loss per cent.
15. On selling 250 cassettes, a man had a gain equal to the selling price of 25 cassettes. Find his gain
per cent.
16. On selling 36 oranges, a vendor loses the selling price of 4 oranges. Find his loss per cent.
17. Toffees are bought at 2 for a rupee and sold at 5 for 3. Find the gain or loss per cent.
18. Coffee costing * 450 per kg was mixed with Chicory costing * 225 per kg in the ratio 5 : 2 for
a certain blend. If the mixture was sold at 405 per kg; find the gain or loss per cent.​

Answer 1

Answer:

sp of 18books =cp of 21 books

LCM of 18and 21 =126

sp of 1 book 126/18 = cp of 1 book 126/21

sp of 1 book 7 = cp of 1 book 6

gain = sp - cp

= 7 - 6

=1

gain %=gain*100/cp

=1*100/6

= 50/3

=16 whole 2/3