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## Early math review

### Course: Early math review>Unit 7

Lesson 3: Comparing and estimating length

# Comparing lengths

Measure and find difference between lengths.

## Comparing lengths by measuring

We can compare lengths by measuring each length and comparing their measures.

### First, let's measure.

Use the ruler to measure the length of each side of the triangle.
What is the length of start color #11accd, start text, S, i, d, e, space, A, end text, end color #11accd?
units

What is the length of start color #1fab54, start text, S, i, d, e, space, B, end text, end color #1fab54?
units

What is the length of start color #aa87ff, start text, S, i, d, e, space, C, end text, end color #aa87ff?
units

### Now, let's compare.

start color #11accd, start text, S, i, d, e, space, A, end text, end color #11accd is
units shorter than start color #aa87ff, start text, S, i, d, e, space, C, end text, end color #aa87ff.

start color #1fab54, start text, S, i, d, e, space, B, end text, end color #1fab54 is
units longer than start color #11accd, start text, S, i, d, e, space, A, end text, end color #11accd.

What is the length of start color #1fab54, start text, S, i, d, e, space, B, end text, end color #1fab54 and start color #aa87ff, start text, S, i, d, e, space, C, end text, end color #aa87ff together?
units

## Want to join the conversation?

• Is there anyway we could get a lesson like this but with a protractor?
• You could, I guess, but I don't recommend it. If you were to use a protractor instead of a ruler, you would need to measure the angles and then use one of three trigonometric ratios (well, six if you count the reciprocal trig ratios) to find the lengths of the sides. I'm gonna assume you're not in grade 10, so I don't recommend this method. I've tried it, and I much prefer a ruler, thank you very much.
• can you compare a different way??
• compare buy subtration or divison the difference is how much greater
• it doesn't matter how hard you try just take your time
• THis is so interesting i love this length measurement
• how long is side a and side b and side c is a b or c longer or shorter
• Side A is 6 cm.
Side B is 8 cm.
Side C is 10 cm.
(You can adjust the ruler to measure the sides)
• Quien tu ere dime socio quien tu eres
• is it a way to get a better aanswr