Question

21 pencils and 29 pens cost rs 79. but if the number of pencils and pens were interchanged, the cost would have reduced by rs 8. find the cost of each pen.

Answer 1

75 79 90 97 9754335789 it re et it ru

Answer 2

Answer:

The cost of a pen is 2 rupees.

Step-by-step explanation:

Let x be the cost of each pencil and y be the cost of each pen,

Since, 21 pencils and 29 pens cost rs 79

⇒ 21x+29y = 79 -----(1)

Also, 29 pencils and 21 pens cost rs 71

⇒ 29x + 21y = 71 -----(2),

29 × equation (1) - 21 × equation (2),

$841y - 441y = 2291 - 1491$

$400y = 800$

$\implies y = 2$

Hence, the cost of each pen is 2 rupees.