Answer:
The distance between the two is:
d=1600km
Hope this helps! :)
Explanation:
so, we know A and B left at the same time, one from city A and the other from city B, they're both moving towards each other, and they met in 5hrs.
now, by the time they met, car A has been running for 5hrs already,
and car B has also been running for 5hrs, so the time for both is the same, when they met, each had been running for 5hrs
if B has a speed rate of "r", then A's speed rate is " r - 10"
now, the next to last paragraph
"If the first automobile had left city A 4 1/2 hours earlier than the other automobile left city B, then the two would have met 150 km away from B."
IF, a big if, but they didn't, they left at the same exact time, so that's just an IF
if A had left 4 1/2 hrs earlier, they'd had met 150km from B
so... by the time A had been running already for 4.5 hrs, car B starts off, goes off and they meet 5hrs later, when they meet, car A would have been running for 5hrs, 4.5 + .5 hrs, but car B would had been running for only half an hour when they met
that means car B met car A half an hour later from when it started, and met A 150kms away from its starting point
that means car B can cover 150km in just half an hour
that gives us a speed rate of 150/.5
which is 300kmh
now, if car B is 300kmh, car A has r-10, or 300-10, or 290kmh
so, car A's rate is really just 290
now, let's say the total distance is AB
so, by the time car A had been running for 5hrs, it had covered a distance of "d"
by the time car B had been running for 5hrs, it had then covered the slack, or " AB - d "