Question

Express the sum of 2222 km and 333 km using the correct number of significant digits.

a.2500 km
b.2550 km
c.2550. km
d.2555 km

Answer 1

The answer is D. 2555 km

Answer 2

Answer : The correct option is, (d) 2555 km

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 that the sum of 2222 km and 333 km.

`2222km+333km`

`\Rightarrow 2555km`

In the given expression, 2222 has 4 significant figures and 333 has 3 significant figures. From this we conclude that least precise number present after the decimal point is 0.

Thus, the answer will be 2555 km.