The marked price of a shirt and trousers are in the ratio 1 : 2. The shopkeeper gives 40% discount on the shirt. If the total discount in the set of the shirt and trousers is 30%, the discount offered on the trousers is:

Question: The marked price of a shirt and trousers are in the ratio 1 : 2. The shopkeeper gives 40% discount on the shirt. If the total discount in the set of the shirt and trousers is 30%, the discount offered on the trousers is:

Solution:
Let,
the price of shirt and trouser be Tk. 100 and Tk. 200 respectively.
Then, price of set of shirt and trouser = Tk. 300.

After giving 30% discount on the set,
Selling Price = 300 - 30% of 300
= 210.

∴ Total Discount on Set = Original price × Discount percentage
= 300 × (30/100)
= 300 × 0.30
= Tk. 90

And Discount on shirt is 20% alone,
SP of shirt alone = 100 - 40% of 100 = 60.
Tk. 40 is the discount on shirt then Tk. 50 must be the discount on the trouser.
So, discount on trouser = (50 × 100)/200 = 25%