Grade 3Math
Reading a ScaleFind out how much one division is, then read the weight
Read the mark that the scale's pointer points to, and find out the weight. You will learn how to find how much one division is, what to be careful about when you read it, and how to choose a scale that fits what you are weighing.
The narration and the pictures are in Japanese. You can hear the same words that are used in class at a Japanese school.
- Video
- 2:40（9 scenes）
- Problems
- 2 problems
Open this lesson in Japanese（はかりの 読み方）
Let's try
Write the math sentence in your notebook first, then open the answer.
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1The whole circle of the scale's dial is 1000 g. The big marks go up by 100 g. Between two big marks next to each other, there are 5 spaces from line to line. When the pointer points 3 divisions past the 400 g mark, what is the weight in grams?
Hint
First, divide the weight between two big marks by the number of spaces to find how much one division is.
Answer
100 ÷ 5 = 20, so one division is 20 g. 400 + 20 + 20 + 20 = 460, so the weight is 460 g.
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2You want to weigh an object that weighs 1500 g. There is a scale that can weigh up to 1000 g and a scale that can weigh up to 3 kg (3000 g). Which one will you use?
Hint
Check whether the object is heavier than the scale's maximum.
Answer
1500 g is heavier than 1000 g, so you can't weigh it on the scale that goes up to 1000 g. Use the scale that goes up to 3 kg (3000 g).
Words in this lesson
- scale marks 目もり
- Lines on a scale or other tools that show how much. There are big marks with numbers, and small marks between them.
- one division 1目もり
- The amount between two lines that are next to each other. To find it, divide the weight between two big marks by the number of spaces between them.
- pan 皿
- The part of a scale where you put the thing you weigh.
- maximum 最大
- The heaviest weight that the scale can weigh.
For parents and guardians
- The names of lessons and the order of topics differ slightly between textbooks. This page follows the content of Japan's national curriculum guidelines (the Course of Study). All problems were made originally for this material.
- When reading a scale, the most important tip is to check "how many grams one division is" before reading the weight that the pointer shows. Count how many spaces (the gaps from one line to the next) there are between two big marks, and divide the weight between the big marks (in g) by that number. The key is to count the spaces, not the number of lines.
- If you have a kitchen scale or a bathroom scale at home, try weighing things around you and reading together the mark that the pointer points to. It also helps your child get into the habit of checking that the pointer points to 0 before weighing.