As indicated in recent researches, plates move away from each other at the rate of 1 centimeter to 12 centimeter every year. Now, based on this finding, we could determine when the Mid-Atlantic Ridge directly at or near the continent of Africa was.
First, let us take the maximum, 12 centimeter, then find how many 12 centimeter there are in 2,400 kilometers.12 centimeters = 0.00012 kilometer2,400 kilometer / 0.00012 kilometer = 20,000,000
Then,
20,000,000 multiplied to 1 year, or: 20,000,000 x 1 year = 20,000,000 years
Therefore, Mid-Atlantic Ridge was directly at or near the continent of Africa 20 million years ago.