Question

In $10$ days, the earth picks up $2.6\times {10}^8$ pounds of dust from the atmosphere. How much dust will it pick up in $45$ days ?

• A. $11.7\times {10}^8$ pounds
• B. $22.3\times {10}^6$ pounds
• C. $17.7\times {10}^7$ pounds
• D. $31.7\times {10}^9$ pounds

Answer 1

The correct option is A $11.7\times {10}^8$ pounds

Let the amount of dust picked up by the earth in $45$ days be $x$ pounds.
Since the amount of dust picked up by the earth and days are in direct proportion.
$\Rightarrow \frac{10}{2.6\times {10}^8}=\frac{45}{x}$
$\Rightarrow x=\frac{45\times 2.6\times {10}^8}{10}=11.7\times {10}^8$ pounds.