Question

If 15 cups of tea and 17 cups of coffee together cost Rs 241, and 25 cups of tea and 13 cups of coffee together cost Rs 279, find the price of each per cup.

• A. Rs 7 and Rs 8
• B. Rs 8 and Rs 9
• C. Rs 8 and Rs 8
• D. Rs 6 and Rs 8

Answer 1

The correct option is A Rs 7 and Rs 8

Let a cup of tea costs Rs x, and a cup of coffee costs Rs y.
Then, from the question, we have
$15x+17y=241$ ............... (1)
$25x+13y=279$ ......... (2)
Multiplying (1) by 5 and (2) by 3, we have
$75x+85y=1205$
and $75x+39y=897$
Subtracting, we get
$46y=368$ or $y=8$
and from (1),
$15x+136=241$ or $15x=105$
$\therefore x=7$
Therefore, the cost of a cup of tea is Rs 7 and the cost of a cup of coffee is Rs 8.