Answer:
For question 10, the answers would be 1/2=.05, 1/5=.02, and 3/4=.75
Explanation:
When working with converting fractions to decimals, you're working with 100. 1/2 of 100 would be .05, which is.50. It could be easy to confuse .05 for 5.0 so remember to use 0.__<-- (your number).
For #12, the answer would be 50%. Out of 40 people, 20 said they do. half of 40 is 20, so like half of 100 is 50, it would be 50%. If you need extra help, KhanAcademy & Virtual Nerd are really great websites! Sorry this isn't the best or easiest explanation..
Good luck! :)