Question

Lake Mead contains approximately 28,945,000 acre feet of water and there are about 326,099 gallons in 1 acre-foot. The approximate number of gallons of water in lake Mead is 9.4x10^a what is the value of a ?

Answer 1

12

Explanation:

Let x be the number of gallons of water in lake Mead.

Given that there is 326099 gallons in 1 acre-foot, we calculate Mead's gallons as:

`1 acrefoot=326099g\\28945000acrefoot=x\\\\x=(28945000acrefoot*326099g)/(1acrefoot)\\\\x=9.4* 10^(12) \ gallons`

We now equate x to
`9.4*10^a`;

`9.4* 10^a=9.4* 10^(12)\\\\a=12`

Hence, a=12