Question

A fruit merchant bought some oranges at the rate of 4 for rs 10 and same amount of oranges at the rate of 5 for rs 10. if he sells whole stock at the rate of 9 for rs 20. find his profit/loss %

Answer 1

he had no profit and no loss

Answer 2

let there be 180 oranges for it is divisible by 4 5 and 9 all the three
so your cost price will be (180 / 4 x 10) + (180 / 5 x 10)
a total of 810
now (360 / 9 x 20) will be your selling price
a total of 800
so I got a loss of rupees 10 on 810
that is 1.235 %