Question

The s.p of 10 pens is equal to the c.p of 15 pens find out the loss or profit percent

Answer 1

let cp of a pen be x
so cost of 15 pens is 15x
sale proceeds of 10 pens is also 15x
so,sp of one pen is 15x/10 which is 1.5x
profit on one pen is 1.5x-x=0.5x=33% on sp=50% on cost