KS2 Primary Maths Age 9-13 - Number and Place Value: Estimation - Explained

The video tutorial explains how to measure the distance from an alligator's eyes to its nose and multiply it by 12 to estimate length differences. It introduces a short method to simplify calculations, avoiding unnecessary long multiplications. The tutorial emphasizes the importance of choosing efficient methods and provides a step-by-step guide to calculating the difference between two alligators' lengths using multiplication without decimals.

What is the initial step in estimating the length of an alligator?

• Measuring the distance from its eyes to its tail

• Measuring the distance from its mouth to its tail

• Measuring the distance from its tail to its nose

• Measuring the distance from its eyes to its nose

How do you calculate the difference in length between the two alligators using the short method?

• Add the two measurements and multiply by 12

• Subtract the smaller measurement from the larger one and multiply by 12

• Multiply each measurement by 12 and then subtract

• Divide the larger measurement by the smaller one and multiply by 12

What is the result of multiplying 2.5 by 12 in the short method?

• 3

• 25

• 30

• 300

Why is it important to choose the most efficient method for solving the problem?

• To make the problem more challenging

• To save time and reduce the number of calculations

• To avoid using a calculator

• To ensure the answer is always correct

What did some students do that resulted in more calculations?

• They multiplied each measurement by 12 and then subtracted

• They added the two measurements together

• They divided the larger measurement by the smaller one

• They measured the distance from the tail to the nose