Answer:
To see the ratio, we should have both in the same unit. We can pass 1/2 hour to minutes, as we know one hour are 60 minutes:
60/2 = 30
So we know half hour are 30 minutes.
Now, we know the ratio 30:45, but we can simplify it, as a fraction.
To simplify it, we will divide both numbers by the same quantity, in this case, divide 30 and 45 by 15 (a it's a divisor):
30/15 = 2 and 45/15 = 3, so the ratio is 30:45, which is equivalent to 2:3