Answer:
given statement is false
Explanation:
given data
first time = 100 minutes
fourth time = 81 minutes
solution
as here time for 1st unit is multiply by learning percentage for obtain time for 2nd unit
so here time for 2nd unit divide by time of 1st unit so 100 is here learning curve
so
× 100 = 81 percent
but it say 90 percent learning curve
so given statement is false