Video Transcript
The can of pineapple is what grams
heavier than the can of corn.
We’re given two pictures here that
can help us find the mass of two different cans of food. We’ve got a can of pineapple and
underneath it a can of corn. Now, it might be quite hard to read
the dials on these scales. But we can see a magnified version
next to them. And we can read these to find out
how heavy each can is. Let’s start with the can of
pineapple.
Can you see where the needle is
pointing? It’s here, isn’t it? Let’s read the scale. It begins at zero. Then we can see 100 grams is
labeled, followed by 200 grams, then 300 grams, and 400 grams. We can stop there because we can
see that the needle is pointing in between the numbers 300 and 400 on the scale. In fact, it’s halfway between,
isn’t it?
Now, do you remember what number is
halfway in between 300 and 400? It’s 350. Although we can’t see the number
350 on the scale, we’ve worked out where it is. And so we know that the mass of the
can of pineapple is 350 grams. And remember, this question is all
about comparing these two masses. So we’re going to have to look at
the second scales. It’s the same set of scales, so we
can see the numbers 100, 200, 300 grams, and so on. But where’s the needle pointing to
this time? We can see that it’s in between the
numbers 200 and 300. And halfway in between the numbers
200 and 300 is 250. The mass of the can of corn is 250
grams.
Now that we’ve measured both
masses, we can compare them. The can of pineapple is what grams
heavier than the can of corn. We know that it’s heavier because
350 is larger than 250. So we know that the can of
pineapple weighs more. But how much more? If we look at the ones digit in our
numbers, we can see that it doesn’t change if we compare them. And they both contain five tens
too, so there’s no change there. But if we compare the hundreds
digit, we can see that there’s a difference of one. 350 is 100 more than 250. And so we can say the can of
pineapple is 100 grams heavier than the can of corn. The missing number is 100.
