Question

In 15 days, the earth picks up 1.2 x 10⁸ kg of dust from the atmosphere. In how many days it will pick up 4.8 x 10⁸ kg of dust?

Answer 1

Let the number of days is x

Weight of dust(pounds)	1.2 x 108	4.8 x 108
Time(days)	15	x

\(\frac{1.2\times 10^8}{15}\) = \(\frac{4.8\times 10^8}{x}\)

On cross multiplication, we get

1.2 x 10⁸ x x = 15 x 4.8 x 10⁸

x = \(\frac{15\times 4.8\times 10^8}{1.2 \times 10^8}\) = 60

Therefore the number of days required to pick up the dust is 60 days