Question

Jessica can swim a lap and 29 and 2/5 second Marta can swim a lap in 28.7 seconds how much faster can marta swim lap and then Jessica

Answer 1

Alright, lets get started.

Jessica can swim a lap in $29\frac{2}{5}$ seconds

Converting it into decimals, $29+\frac{2}{5}$

Means $29+0.4 = 29.4$ seconds

Means Jessica can swim a lap in 29.4 seconds

Marta can swim a lap in 28.7 seconds.

So, Martha is faster than Jessica by $29.4-28.7=0.7$ seconds

It means Marta is 0.7 seconds faster than Jessica.   :  Answer

Hope it will help :)