Answer:
Joy definitely does have enough soup for 22 people.
Step-by-step explanation:
Upper Bound: 285ml turn it to 0.285l 10÷2=5
280ml
Lower Bound: 275ml turn it to 0.275l
Upper Bound: 6.75l 0.5÷2=0.25
6.5 Litters
Lower Bound:6.25l
6.75÷0.275=24.54 or 25
6.25÷0.285=21.92 or 22
22 < 25 Joy definitely does have enough soup for 22 people.