I am in 6th grade and have a math problem that I need help with. How can you use four rods that measure 2cm, 5cm, 7cm and 9cm to measure a length of 1cm?
Here's one way:
Use the 2cm rod twice:
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To measure a length of 1cm using the four rods, you can use the concept of subtraction. Here's how:
1. Start by placing the 2cm rod horizontally.
2. Place the 5cm rod vertically, starting from the end of the 2cm rod.
3. Subtract 2cm from 5cm, which leaves you with 3cm.
4. Place the 7cm rod vertically, starting from the end of the 5cm rod.
5. Subtract 3cm from 7cm, which leaves you with 4cm.
6. Finally, place the 9cm rod vertically, starting from the end of the 7cm rod.
7. Subtract 4cm from 9cm, which leaves you with 5cm.
By subtracting the lengths of the previously placed rods from the longer rods, you were able to measure a length of 1cm using the given rods.