800/100 = 8
800 is 100 times as much as 8
Let's first break it down to the time 8 people need for one wall. That would be 10 minutes, right? If one person would have to do it in stead of 8, you'd expect him to take 80 minutes.
To paint 7 walls, he would nee 7x80 = 560 minutes. 10 people would do that 10 times faster, ie., 56 minutes.
I know puzzles like these always have a mindtrick. Did I miss anything?? ;-)
50 divided by 8 = 6.25
1oz perfume = $6.25
110 divided by 17 = 6.4705
1oz perfume = $6.4705
Therefore the second option is cheaper
20 000 * 0.08(8%)= 1600
1600 * 20(years) = 32 000
Therefore you would have $32 000 after 20 years
