Question

Suppose you have a bucket of sand containing 5.5 billion grains of sand ( 5.5×109 grains). Most of the grains of sand are white, but there are some brown grains mixed evenly throughout. If the concentration of brown sand is 2.0% , how many grains of brown sand are in the bucket?

Answer 1

Answer:

  1.1×10^8

Step-by-step explanation:

2% of 5.5 billion is ...

  2×10^-2 × 5.5×10^9 = 11×10^7 = 1.1×10^8

About 1.1×10^8 grains of brown sand are in the bucket.

Answer 2

Answer:

Grains of brown sand are in the bucket are $1.1\times 10^8 grains$.

Step-by-step explanation:

Total number sand grains in the bucket =$5.5\times 10^9 grain$

Concentration of brown sand grains = 2.0%

Number of brown brain in the bucket be x

$\%=\frac{\text{Brown sand grains}}{\text{Total sand grains}}\times 100$

$2.0\%=\frac{x}{5.5\times 10^9 grain}\times 100$

$x=1.1\times 10^8 grains$

Grains of brown sand are in the bucket are $1.1\times 10^8 grains$.