- Si un comerciante vendiera a S/.11 cada calculadora que tiene, ganaría S/.60 en total, pero si decide venderlas a S/.6 cada una, pierde S/

- If a trader sells to S / .11 each
calculator that is, win S / .60 in
total, but if you decide to sell a S / .6 each
one loses S / 20 in total. How many
calculators have to sell?