For the same distance, the ship can find the distance with a downwind of 30 kilometers per hour and a headwind of 22 kilometers per hour, and the time difference is 4 hours. Search by speed ratio

The answer 4 divided by (15- 1 1) and then multiplied by 1 1 is actually a simplification of dividing 4 by (30-22) and then multiplying it by 22. 4x22 is the distance difference within the time difference, and 30-22 is the speed difference, so distance difference/speed difference = the time taken to complete the distance in the downstream situation, so distance difference/speed difference x downstream speed = distance. That is 22x4/(30-22)x30= distance, that is, 330 kilometers.

What you call "the difference between time difference and speed ratio" is the distance.

Your question should be "What is the time difference divided by the speed difference?"? Because you were cheated by 4/( 15- 1 1), it was actually 4x22/(30-22), and the distance difference/speed difference.

The following students should not denigrate the idea of solving problems. Mathematics is a game, and some problems have many solutions.

If you think it's good to be simple, then I ask you, "1+ 1=2" is simple? Why do you think =2?