Our current best estimate is that the western Grand Canyon in Arizona began to be excavated by riser erosion about 6 million years ago. The greatest depth of the Grand Canyon is about 1 .6 km. Required:a. Is the mean (average) rate that the Grand Canyon has been eroded into the Color-ado Plateau during the past 6 million years. expressed in millimeters per year? Show your work below. b. If erosion of the Grand Canyon proceeded at that rate during the most recent century, how much deeper is it today than it was on the day you were born? Show your work.

A. If  the mean (average) rate of the Grand Canyon has been eroded into the Color-ado Plateau during the past 6 million years, the it being expressed in millimeter would be:

Estimated time since erosion began = 6 million years

Greatest depth of canyon = 1.6km

Average is a number expressing the central value in a set of data which is the mode, median or mean which is calculated by dividing the sum of values in their set by their numbers.

Therefore, the mean rate of erosion in millimeter per year:

Mean rate = Depth of canyon / time

Depth of canyon in millimeter:

1 km = 1000000 mm

1.6km = (1.6 × 1000000) = 1,600,000 mm

Mean rate = 1,600,000mm/ 6,000,000 years

Mean rate = 0.26666 mm/year

Mean rate approximately = 0.267 mm/year

B. If erosion of the Grand Canyon proceeded at that rate during the most recent century, the depth of it today than it was the day i was born would be:

If  the rate of erosion = 0.267mm/year

Date difference = 27 years 55 days

Total number of days = (27 *365) + 55 = 9,910 days

Rate of erosion per day = 0.267 / 365 = 0.0007315 mm / day

Therefore, the Change in depth from date of birth till today: 0.0007315 mm/day × 9,910 days = 7.2492328 mm

Approximately = 7.25 mm deeper

Read more about average here:

link

0.267mm/yr

7.25 mm

Explanation:

Given the following:

Estimated time since erosion began = 6 million years

Greatest depth of canyon = about 1.6km

The mean rate of erosion in millimeter per year:

Mean rate = Depth of canyon / time

Depth of canyon in millimeter:

1 km = 1000000 mm

1.6km = (1.6 × 1000000) = 1,600,000 mm

Mean rate = 1,600,000mm/ 6,000,000 years

Mean rate = 0.26666 mm/yr

Mean rate = 0.267 mm/year

B.) If rate of erosion = 0.267mm/yr

Date of birth = 30 / 10 / 1992

Today's date = 5 / 9 / 2020

Date difference = 27 years 55 days

Total number of days = (27 *365) + 55 = 9,910 days

Rate of erosion per day = 0.267 / 365 = 0.0007315 mm / day

Change in depth from date of birth till today:

0.0007315 mm/day × 9,910 days

= 7.2492328 mm

= 7.25 mm deeper