Answer:
49 units
Explanation:
10.50u ≥ 200 + 6.40u solve for u....
4.10u ≥ 200 (subtract 6.40u to both sides)
u ≥ 200/4.10 (divide both sides by 4.10)
u ≥ 48.78
Any number of units greater than 48.78, but they can't sell parts of a unit, so 49 is the minimum number of units that need to be sold to make a profit