-3 1/2 because if you do 2.8 times 1 and 1/4 you get 3.5 and 3.5 as a fraction is 3 1/2
Speed of the waves because a wave can get faster
Sorry, what exactly is the question?
Let's make it an expression.
Three half's= 3/2 Plus= + one fifth= 1/5
We need to turn 3/2 and 1/5 so that they have the same denominator. Let's use 10.
3/2→15/10 1/5→2/10
15/10+2/10=17/10=1 7/10
So, three half's plus one fifth is 1 7/10.
