What are Significant figures:

Another method of approximating an answer is to round off using significant figures.

With the number **738,249**, the **7** is the most significant digit, because it tells us that the number is 7 hundred thousand and something. Then the** 3** is the next most significant, and so on.

With the number **0.00321**, the** 3** is the most significant digit, because it tells us that the number is 3 thousandth and something. Then the **2** is the next most significant, and so on.

Be careful with numbers with a zero, such as **90123**, the **9** is the first significant figure and 0 the second, because of its value as a place holder.

Round off a number to a certain number of significant figures, usually to **1**, **2** or **3** significant figures.

Your Turn:

What is 1.99 correct to 2 sfs?

Enter your answer here: