Question

In adding the measurements 11.074 m, 18.2 m, and 16.943 m, what should be the number of significant figures in the result?

Answer 1

18.2m has the least amount of significant figures (3) so the final product should have that many significant figures. After adding all of the numbers together you get 46.217 m but we need 3 significant figures for this problem so you simply round it to 46.2 m

Answer 2

Answer : The correct answer will be 46.2 m.

Explanation :

Significant figures : The figures in a number which express the value -the magnitude of a quantity to a specific degree of accuracy is known as significant digits.

The rule apply for the addition and subtraction is :

The least precise number present after the decimal point determines the number of significant figures in the answer.

Given : The sum of the measured values 11.074 m, 18.2 m, and 16.943 m.

`11.074m+18.2m+16.943m`

`\Rightarrow 46.217m`

In the given expression, 11.074 has 5 significant figures, 18.2 has 3 significant figures and 16.943 has 5 significant figures. From this we conclude that least precise number present after the decimal point is 1.

Thus, the answer will be 46.2 m.