Brookstone Rc Sailboat

There

Statement several ways to solve these problems without resorting to formal algebra. The idea is to play with watermelons and melons, giving values \u200b\u200bto their weights, putting more together, and so on.

A nice way to solve is this: if three and four melons, watermelons weigh 13 and four watermelons and three cantaloupes weigh 15, to put it all together we have seven and seven melons watermelons weigh 28. Now, if we make seven parts, each couple have a watermelon and a cantaloupe weigh 4.

Having this idea in mind, we return to a track in the beginning. As three and four melons watermelons weigh 13, and is very close to being matched quantities, try to reach a similar figure.

now know that three watermelons and three cantaloupes are three couples as we have done before, which in total weighed 4 + 4 + 4 = 12. That means that the melon is most in the initial track weighs 13 to 12 = 1kg, so that each watermelon weighs 3kg.

We found that both tracks are true, ie three and four melons, watermelons weigh 9 + 4 = 13 and four watermelons and three cantaloupes weigh 12 + 3 = 15.