Let the amount Tom does = x
Then Larissa’s time would be 3x( 3 times the amount of Tom)
And Neal would also be 3x
The total of the 3 is 84 hours so as an equation you have:
X + 3x + 3x = 84
Combine like terms
7x = 84
Divide both sides by 7
X = 84/7
X = 12 hours
Tom = x, so Tom exercised for 12 hours.
