If 25,000 crystals cost 1.5 million then how much is 1 crystal

60$

Step-by-step explanation:

Step-by-step explanation:

1. The trains are moving toward each other at a total speed of 50 +20 = 70 miles per hour. Together, they cover the 210 mile distance in ...

  time = distance/speed

  time = 210 mi/(70 mi/h) = 3 h

The trains collide after 3 hours.

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2. The fly is closing with the freight train at a speed of 100 +20 = 120 miles per hour. Together, the fly and the train cover the initial 210 mile distance in ...

  (210 mi)/(120 mi/h) = 7/4 h = 1 hour 45 minutes

The fly first meets the oncoming freight train after 1 h 45 min.

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3. The fly is flying for all three hours before the trains collide, so, at 100 miles per hour, will fly 300 miles.