The total distance going from home to work = total distance going from work to home

In the 1st case David drove @ an average speed of 45 miles per hour so distance \(d = 45 h1\)where \(h1\)is the time taken to complete the distance

In the 2nd case David drove @ an average speed of 60 miles per hour so distance \(d = 60 h2\)where \(h2\)is the time taken to complete the return journey from work to home

Given,

\(h1 + h2 = 2\)

we get,\(h1 = 2 - h2\)

Since distance is equal for going to work from home and coming back to home from work

\(45h1 = 60h2\)

hence, \(45(2 - h2) = 60 h2\)

solve for h2 it should equal\(\frac{90}{105}\)

Solve for D by replacing value of h2 in the eqn \(60* h2\)

\(d =\frac{360}{7}\)

(C)

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