Question

A typical aerobic walker on a track covers a lap (0.25 miles) in about 3.4 minutes. A champion marathon runner takes about five minutes to cover a mile. If an aerobic walker completed the Boston Marathon (42.16 km), how many minutes would you expect him to fall behind the winner?

Answer 1

Answer:226.61 minutes behind

Explanation:

The fisrt consideration you need to make is that the aerobic wlaker will keep up the same speed in the whole marathon. The you can apply a simple rule  of three (see picture attached)

How many minutes will it take to complete 42.16 km it it takes him 3.4 minutes to complete 0.25 miles? First you need o unify length units. 1 mile is 1.6 km, then 0.25 miles are equivalent to 0.25 miles*1.6km/1mile= 0.4 km (se picture attached, rule of three has been applied)

Then if it takes 3.4 minutes to complete 0.4 km, it will take him 42.16km*3.4min/0.4km=358,36 min

Using the same rule of three, for the champion then, he takes  5 minutes per mile, then  to complete a km it takes him: 1km*5min/1.6km=3.125 min. then again to complete 42.16 km, it takes him: 42.16km*3.125min/1km=131,75 min

Then itm takes 131.75 minutes to the champion amrathon to complete it and 358.36 min to the aerobic  walker. So he will arrive 358.36-131.75=226.61 minutes behind