Sometimes we need to measure an object and know the exact measurement. Yet, sometimes you may not need to know the exact measurement. When we estimate, we do not just guess. We need to use some tool of measurement. Our tools could be a ruler or a measuring tape.

Let’s look at some examples. Then you will have some online exercises to complete.

### Practice question 1:

The length of the African Elephant is 5 metres long. Can you estimate the length of the Blue Whale? Use the elephant to help you estimate the length of the whale.

### Practice question 2:

Consider, the man below. He is at average height. How many humans of similar height can equal the length of the whale?

Explain you answer.

### Practice question 3:

Can you estimate the height of this eight year old boy? What tool would you use?

**Practice answers:**

- Practice 1 answer: If you estimate the length of the Blue Whale as 25 m, you are correct.
- Practice question 1: Approximately 14 men will measure up to the Blue Whale.
- If you say a meter stick or a measuring tape you are correct.

**Time for some questions:**