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 6.0% , how many grains of brown sand are in the bucket?

brown grains

If the concentration of brown sand is 6.0 ppm, how many grains of brown sand are in the bucket?

brown grains

If the concentration of brown sand is 6.0 ppb, how many grains of brown sand are in the bucket?

brown grains

Answer 1

Explanation:

5.5 billion grains of sand ( 5.5×109 grains)

If the concentration of brown sand is 6.0% , how many grains of brown sand are in the bucket?

Number of grains = Concentration of brown side *  Bucket of sand

Brown grains = 0.06 *  5.5×10^9  = 0.33 x 10^9 = 3.3 x 10^8 grains

If the concentration of brown sand is 6.0 ppm, how many grains of brown sand are in the bucket?

Number of grains = Concentration of brown side *  Bucket of sand

6ppm = 6 / 1000000 = 0.000006

Brown grains =  0.000006  *  5.5×10^9  = 3.3 x 10^4 grains

If the concentration of brown sand is 6.0 ppb, how many grains of brown sand are in the bucket?

Number of grains = Concentration of brown side *  Bucket of sand

6ppb = 6 / 1000000000 = 0.000000006

Brown grains =  0.000000006  *  5.5×10^9  = 3.3 x 10^1 = 33 grains