Because your calculator is broken. Seriously; 30 divided by half (0.5) is 60 and 60 + 10 = 70 So, 30 cut in half (30/2) is 15 but 30 DIVIDED BY half (30/0.5) is 60.
0.016666666666etc.
20.
30 divided by 1/2 is 60.
40
one half of 30 is 15 LOOPDOP says the question was 30 / 0.5 which = 60 same as 30 divided by 1/2 = 30 multiplied by 2/1 = 60
70: 30 divided by 1/2=60+10=70 trick: not 30 divided by 2
37.5
60 minutes in an hour divided by 2( in other words cut in half) is 30, half an hour.
40
40
10