A and B both drive from a to 8. A travels 65 kilometers per hour, B 42 kilometers per hour. B starts 2 hours before a starts. After a few hours, a exceeds B by 8 kilometers?

(42 × 2 + 8) △ 65-42) = (84 + 8) △ 23, = 92 △ 23, = 4 (hours). Answer: after another 4 hours, car a exceeds car B by 8 km

A and B both drive from a to B. car a travels 65 kilometers per hour, while car B travels 42 kilometers per hour. Car B starts two hours before car a starts. After a few hours, car a exceeds car B by 8 kilometers?

(2×42+8)÷(65-42)
=4 (hours)

A and B both drive from a to B. car a travels 65 kilometers per hour and car B 45 kilometers per hour. Car B starts two hours before car a starts
How many hours does car a catch up with car B?

45 × 2 ÷ (65-45) = 4.5 hours
A: car a overtakes car B in 4.5 hours

A and B drive from a to B at the same time. A travels 65 kilometers per hour, B 42 kilometers per hour. B starts two hours first, then a starts again, and then a few hours later
When car a exceeds car B by 8 km?

Distance difference = 42x2 + 8 = 92KM
Speed difference = 65-42 = 23km / h
Time = distance difference △ speed difference = 92 △ 23 = 4 (hours)

A and B start from a place 180km away to B. A starts at 1.5 p.m. later than B and arrives at the same time. The speed ratio of a and B is 4:3. How many km does a travel per hour?

40km / h, let a's speed be 4x, B's speed be 3x, this can satisfy the condition that the speed ratio is 4:3, let B's travel time be t, then a's time is t-1.5, and then the equation is formulated. 4x (t-1.5) = 180, 3xt = 180, that is 4X (t-1.5) = 3xt, solve t = 6, and then a's speed is 40km / h
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A and B both drive from a to 8. A travels 65 kilometers per hour, B 42 kilometers per hour. B starts 2 hours before a starts. After a few hours, a exceeds B by 8 kilometers?