Question

What is the answer, with the correct number of significant figures, for this problem? 4.392g + 102.40g + 2.51g =_______.

Answer 1

Answer : The correct answer will be, $109.30g$

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.

The given expression is:

$4.392g+102.40g+2.51g$

$\Rightarrow 109.302g$

In the given expression, 4.392 has 4 significant figures, 102.40 has 5 significant figures and 2.51 has 2 significant figures. From this we conclude that least precise number present after the decimal point is 2.

Thus, the answer will be $109.30g$