Estimate by rounding as indicated.
-There are 27,878,400 square feet in one square mile. How many square feet are there in 33 square miles? Estimate by rounding the number of square feet in one square mile to the nearest ten million and the number of square miles to the nearest ten. Also find the exact answer.
A) Estimate: $840,000,000 \mathrm{sq} \mathrm{ft}$; exact: $919,974,000 \mathrm{sq} \mathrm{ft}$
B) Estimate: 900,000,000 sq ft; exact: 919,987,200 sq ft
C) Estimate: 840,000,000 sq ft; exact: 919,987,200 sq ft
D) Estimate: 900,000,000 sq ft; exact: 919,974,000 sq ft

Question

Quizplus · Accepted Answer

Rounding 27,878,400 to the nearest ten million gives 30,000,000. Rounding 33 to the nearest ten gives 30. The estimate is 30,000,000 * 30 = 900,000,000 sq ft. The exact calculation is 27,878,400 * 33 = 919,987,200 sq ft.

Estimate by Rounding as Indicated 840,000,000sqft840,000,000 \mathrm{sq} \mathrm{ft}840,000,000sqft ; Exact 919,974,000sqft919,974,000 \mathrm{sq} \mathrm{ft}919,974,000sqft

Estimate by Rounding as Indicated $840,000,000 \mathrm{sq} \mathrm{ft}$ ; Exact $919,974,000 \mathrm{sq} \mathrm{ft}$