What decimal point is between 1.5 and 1.7 and i know its 1.6 but on my homework it wont say 1.6 it says 1.625 , 1.25 , 1.75 , 1.83

It doesn't matter what's between it as long as it is within that range, if that makes any sense.

1.25 isn't.
1.75 isn't.
1.83 isn't.

1.625 would be your answer. :)

The answer is 41.7 because 1.39 times 30 is 41.7