Question

A shopkeeper earns a profit of Rs 1 on selling one pen and suffers a loss of Rs., 30 paise on selling one pencil in a particular month he incurs a loss of Rs 5 on that month he sold 40 pens how many pencil did he sold in that month

Answer 1

c.p of pen=1
c.p of pencil=1
c.p-s.p=loss

(40+x)-(80+7/10*x)=5
(40+x-80-7/10*x)=5
3/10*x-40=5
3/10*x=45
x=150