If a parent gave a child money to buy a suit, and the child assumed that the suit would cost at least 700 NIS. The parent would have wanted him to buy a cheaper suit but ended up giving the child 700 NIS. The child found a suit for 228 NIS and was satisfied. Does the child have to return the rest of the money?
Yes, the money must be given back to the parent. The intention of the parent was not to give the child a monetary gift, but to give him money with which to purchase a suit. If the child was pleased with a cheaper suit than he expected, the remainder therefore returns to the parent.