The order of the 3 books does not matter so its the number of combinations of 3 from 45
b is the correct choice
Answer: 2.065
Step-by-step explanation:
Answer:
43.96
Step-by-step explanation:warning might be wrong
Just guess and check. For example, for the first on the left, I guessed 3 to begin with. 3 + 3 + 3 = 9, but 10 + 3 = 13, so 3 is not the answer. I then guessed 5. 5 + 5 + 5= 15, and 10 + 5= 15, so star = 5.
6 foot makes 4.5 foot shadow
1 foot makes=4.5/6
so 50 foot =4.5/6*50 = tree makes 37.5 foot shadow
