Question

Two planes started at the same time from two airports which are 2300 miles apart and flew toward each other. one plane few 310 mph, and the other flew 390mph. in how many hours were the planes still 200 miles apart?

Answer 1

They're travelling towards each other;
Effective speed= 310+390 = 700mph

Distance = 2100 (omit 200m as we want to know the time when they're still 200m apart)

Time = distance/ speed
T= 2100 / 700
T= 3hrs