Shane worked 8 hours per day for 3 days. andrew worked 6 hours per day for 4 days. if the normal working week is 36 hours, which man worked the highest percentage?

Shane:
8 x 3 = 24 Because it is 8h per day for 3 days. Per is like times
24h out of 36  24/36 GCF is 12 divide to and bottom by 12
24 / 12 is 2   36 / 12 is 3  2/3    Shane worked for 2/3 of 36h
Percentage: 100% / 3 (because there is 3 parts)= 33.333333333333 
33.33333333333 x 2 (because it is there is 2 parts needed) = 66.6666666666%
Shane has worked for 66.6666666666% of 36 hours
 
 Andrew:
 4 x 6 = 24 
Hey did you realise, the 24 is exactly the same! So the fraction would still be 2/3 of 36, and so on, there percentage is still the same, it's still 66.6666666666%

Both of Andrew and Shane has worked for the exact same time, therefore they have the exact same percentage         

12 oz = 1.15
24 oz = 2.79
Let's see if 2x12oz is equal, less, or more than the 24oz.
1.15 x 2 = 2.30
2.30<2.79
The 12 oz is a better buy.