1.2 meters = 120 centimeters
amount of increase = 120-80 = 40 centimeters
40 ÷ 80 = 0.5 = 50%
There was a 50% increase.
30,00 watts.
Think of the metric system like this: K H D B D C M
Now. you have kilo at the begining and milli at the end. To transition from left to right you multiply by 10 each time. To transition from right to left, you divide by 10 each time.
Alright, so since 20/100=1/5, and 1/5 of 45=9, 20% off of 45=9 and 45-9=36 dollar sale. Since 30=30/100, we can divide 95 by 100 and multiply that by 30 to get 0.95*30=28.5. 95-28.5=66.5
Next, we need to find 8% of 36+66.5=102.5. 8=8/100, so we divide 102.5 by 100 and multiply it by 8, getting 1.025*8=8.2