WEBVTT
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What is the mass of the bread roll?
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In this question, we have to use the balancing scales and the gram weights to find the mass of the bread roll.
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We can see that the scales are balanced, which means that the mass is equal on each side.
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If we add together all of the gram weights that we used to balance the scale, that will tell us the mass of the bread roll.
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The largest gram weight has the number 50.
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This is worth 50 grams.
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There are two 10-gram weights and a one-gram weight.
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Let’s add these gram weights together.
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Let’s start by adding in the ones column.
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Zero plus zero plus zero plus one gives us a total of one.
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Next, we need to add in the tens column.
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Five plus one plus one gives us a total of seven.
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50 plus 10 plus 10 plus one equals 71 grams.
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The mass of the bread roll is 71 grams.