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
Answer:
the current length x (in meters) of an apatosaurus is:
x = 22.50m