By hypothesis, There's 15 minutes between work and home. So going to work takes 15 minutes, and going back home from work takes 15 minutes, making a total of 30 minutes per day going back and forth to work. Let x be the time spent in a 5 day work week travelling back and forth to work, using the rule of three:
1 day --> 30 minutes 5 days --> x minutes
x = (5*30)/1 = 5*30 = 150 minutes.
150 minutes = 150/60 = 2.5 hours.
So in a 5 day work week, the time spent travelling back and forth to work is 2.5 hours, or 150 minutes.
SOLVING (if needed) Substitute 2 + .5w in for l in the second equation and solve for w. 2(2 + .5w) + 2w = 40 4 + w + 2w = 40 Combine like terms and subtract 4 from both sides 3w = 36 Divide both sides by 3 w = 12 in. l = 2 + .5w l = 2 + .5(12) l = 8 in.