If you flip three fair coins, what is the probability that the first two flips will both be heads, and the third flip will be either heads or tails?

25%. With a 50% chance of it landing heads the first time, you need to multiply it by the percentage that you have that it will land on heads again, which is 50. 50% of 50 is 25, and then having it land on either heads or tails for the third time is guaranteed, so multiply that probability (100%) by the previous 25% which ends up being simply 25%

Yes. there is a constant ratio of number of calories to gram of protein.12/3=24/4=32/8=44/11=4