Question

Be sure to answer all parts. Carry out the following operations as if it were a calculation of real experimental results. Express the answer with the correct number of significant figures. (3.26 × 10−3 mg) − (7.88 × 10−5 mg ) Answer Units mg Enter your answer in standard form. Do not use scientific notation.

Answer 1

Answer : The answer in standard form is, 0.00318 mg.

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.

As we are given :

`(3.26*10^(-3))mg-(7.88* 10^(-5))mg`

First we have to convert scientific notation into standard form.

`\Rightarrow 0.00326mg-0.0000788mg`

`\Rightarrow 0.00318mg`

As per rule, the least precise number present after the decimal point is 5. So, the answer will be, 0.00318 mg.