Physics

# Subtract $2.5 \times {10}^{4}$ from $3.9 \times {10}^{5}$ and give the answer to correct number of significant figures.

$3.6\times 10^5$

##### SOLUTION
We have $3.9 \times 10^5- 2.5 \times 10^4$
$= 3.9 \times 10^5- 0.25 \times 10^5$
$=3.65 \times 10^5$
But our answer should be rounded off upto two significant digits.
So the ans is $3.6\times 10^5$

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Single Correct Medium Published on 18th 08, 2020
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