Explanation : Enzo has 7 pesos, and a ballpoint pen is 2 pesos + an additional 2 pesos, he spent 4, now we have 3 left. A notebook is 3 pesos - a single peso, he just spend 2 more pesos leaving him with only 1 peso left. The crayons cost 2 pesos - a single peso which means he used his remaining peso, 4 + 2 + 1 = 7.
