Aaron Miguel purchased a ballpen at a cost of 420 pesos a dozen. at what price will have to sell each ballpen in order to realize a 40% profit on cost?
step 1
Divide 420 pesos by a dozen
420/12=35 pesos per ballpen
step 2
Increase price of each ballpen by a 40%
Remember that
100%+40%=140%=140/100=1.40
so
1.40*35=49 pesos per ballpen
therefore
the answer is
49 pesos per ballpen