Question Video: Indirectly Comparing the Masses of Two Objects by Comparing Them Both to a Third Object Mathematics • 1st Grade

Which item is heaviest?

02:16

Video Transcript

Which item is heaviest? Is it the watermelon or the pot of jam?

In this question, we need to spot the heaviest item. We know that the word “heaviest” means that it weighs the most. And If we had a set of balancing scales like these and we put a watermelon on one end and that pot of jam on the other, we’d be able to see straight away which item was heaviest. But in this question, we’re not comparing the masses of these two objects directly like this, even though it’d be easier. We’re comparing both objects with a third object. Can you spot it? It’s a bottle of milk. First, we’re going to compare a pot of jam with the bottle of milk. And then, we’re going to compare the watermelon with the bottle of milk. And we’re going to use this to help us work out which is heaviest out of the watermelon and the pot of jam.

So what can we see in the first picture? Well, in this picture, we’re comparing the pot of jam with the bottle of milk. And we can see that the end of the scales that has the bottle of milk on it has gone down. This has meant that the end with the pot of jam on it has gone up in the air. And this tells us something about how heavy these items are, doesn’t it? What can we say about the pot of jam? The pot of jam is lighter than the bottle of milk.

On the second set of scales, we’re comparing the watermelon with the bottle of milk. This time, it’s the end with the watermelon on that’s gone down, and this has lifted the end with the bottle of milk on it up in the air. What can we say about the watermelon then? The watermelon is heavier than the bottle of milk. And we can use what we’ve found to compare our two objects. Because we know the pot of jam is lighter than the bottle of milk but the watermelon is heavier than the bottle of milk, we can tell which item is heaviest. It’s the watermelon. The watermelon must be heaviest.

Nagwa uses cookies to ensure you get the best experience on our website. Learn more about our Privacy Policy.