Question

Use proportional thinking to answer the question. Explain how you got an answer without using pencil and paper or a calculator.

If 10% of a number is 4.3, what is
20% of the number?

Answer 1

8.6

Explanation:

If we know 10% of a number is 4.3, we can easily find 20% of the number as well.

We know 20% is 2 times 10%.

Therefore,

• 2 x 4.3
• 8.6