The water level in an ocean changes at an average rate of 3 meters per hour. At this rate, how many hours would it take for the water level to change 12 meters?

4 hours

Step-by-step explanation:

The water level changes at an average rate of 3 meters per hour.

The question wants to know how long it will take for the ocean water level to change 12 meters.

You can use direct proportion:

1 hour     :  3 meters

x hours   : 12 meters

Cross multiply to get:

3x = 12

x = 12 / 3

= 4 hours

the simplified form is

step-by-step explanation:

we want to simplify the expression,

let us change the middle bar to a normal division sign to obtain,

we multiply the first fraction by the reciprocal of the second fraction to obtain,

we factor to obtain,

we cancel the common factors to get,

we simplify to get,

the correct answer is b