## Chemistry: Molecular Approach (4th Edition)

Using dimensional analysis gives: $1 acre = 43,560 ft^{2}, 1 mile = 5280 ft, 1 mile^{2} = 27878400 ft^{2}$ $435 \times 43,560 ft^{2} = 18,948,600 ft^{2}$ $18,948,600 / 27878400 = 0.680 mile^{2}$
Using dimensional analysis gives: $1 acre = 43,560 ft^{2}, 1 mile = 5280 ft, 1 mile^{2} = 27878400 ft^{2}$ $435 \times 43,560 ft^{2} = 18,948,600 ft^{2}$ $18,948,600 / 27878400 = 0.680 mile^{2}$