Answer:
804 feet
Explanation:
Given: Dimension of a basketball court is 84 feet by 50 feet.
Considering the shape of basketball court is in rectangle shape.
∴ Finding the perimeter of rectangle to know total number of feet in one round.
Perimeter of rectangle=

where, l= length
w= width
∴ Perimeter of rectangular court=

⇒ Perimeter of rectangular court=

Opening parenthesis
⇒ Perimeter of rectangular court=

Hence, Brett run 268 feet in one round of warm up.
As given, Brett ran around the court 3 times.
∴ Total number of feet=

Hence, Brett jog for 804 feet.