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The answer to the fourth question on page 54 of the first volume of mathematics learning evaluation in the fifth grade of primary school
Party A and Party B respectively walk in opposite directions at the same time in Party A and Party B, meet at E, Party A continues to walk towards Party B, Party B takes a rest for 14 minutes, and then continues to walk towards Party A. Party A and Party B turn back immediately after arriving at Party B and Party A respectively, and still meet at E ... Knowing that A walks 60 meters per minute and B walks 80 meters per minute, how many meters are there between A and B?

Solution: treat the whole process as a unit 1.

The speed ratio between Party A and Party B is 60: 80 = 3: 4.

The distance a of point E is 3/7 of the whole journey.

When we meet for the second time, one * * * is three times.

After resting 14 minutes, A walked 60× 14=840 meters.

After the first meeting, B left 3/7×2=6/7.

Then the distance traveled by A is 6/7×3/4=9/ 14.

In fact, A left 4/7×2=8/7.

Then during B's rest, A left 8/7-9/ 14= 1/2.

Then the whole journey = 840/( 1/2) = 1680m.

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