Question

the price of the 5 pens and 4 pencils is 70 rupees the price of 3 pens and 7 pencils is 65 rupees? what is the price of a pen? what is the price of pencils?​

Answer 1

Step-by-step explanation:

let the price of one pen be x and price of. 1 pen be y

5x+4y=70 ....(1)

3x+7y=65 .....(2)

from equation (1)

we get x=70-4y/5 ...... (3)

by putting the value of x in equation (2)

3(70-4y/5)+7y=65

210-12y+35y=65*5

210+23y=325

23y=325-210

y=115/23=5

y=5

now .by putting the value of y in equation (3)

we get x=70-4(5)/5

x=70-20/5

x=50/5=10

x=10

hence,cost of one pen is 10Rs and cost of one pencil is 5Rs

hope helpful....