Question

the cost of 7 pens is 21 rs .find the cost of 11 such pens ?​

Answer 1

if the cost of 7 pens if 21 rs

then cost of 11 pens is 33 rs

Answer 2

Answer:

Given total cost of 5 pens and 10 pencil = Rs 30

5 pens + 10 pencils = 30

pens + 2 pencils = 1

also given pen cost 3 more than a pencil

i.e, pen = 3 + pencil.

pen - pencil = 3

pens + 2 pencils = 6

_______________

-3 pencils = -3

pencils = 1

pen - 1 = 3

pen = 4

cost of pencils = 1 cost of pen = 4