The natural history museum has a 1: 75 scale model of an apatosaurus dinosaur. the length of the model is 30 centimeters. find the actual length x (in meters) of an apatosaurus.

For this case what we should do is write the expression of the ratios.
 We have then:
 (75/1) = (x / 30)
 Clearing x we have:
 x = 30 * (75/1)
 x = 2250 cm
 Then, you must take into account the following conversion:
 1m = 100cm
 We have then:
 x = 2250 * (1/100) = 22.50m
  
 the current length x (in meters) of an apatosaurus is:
 x = 22.50m

This makes absolutely no sense at all young man/women