Handball = 44 minutes
Cycling = 8 minutes
Jogging = 8 minutes
Let's use the following variables
j = Time Joel jogs.
h = Time Joel plays handball
c = Time Joel cycles.
Now make some expressions to describe the problem.
13j + 11h + 14c = 700
j=c
h = 60 - j - c
Now substitute c for j in the expressions.
13c + 11h + 14c = 700
h = 60 - c - c = 60 - 2c
Now substitute 60 - 2c for h
13c + 11(60 - 2c) + 14c = 700
And solve for c
13c + 11(60 - 2c) + 14c = 700
13c + 660 - 22c + 14c = 700
13c - 22c + 14c = 40
5c = 40
c = 8
So we now know the 8 minutes were spent cycling. And because of j=c, we also know that 8 minutes were spent jogging. And finally, because of h=60-2c, we know that 44 minutes were spent playing handball.
