10. B
11. D
12. C
13. B
14. B
15. D
Yep!
Weighing #1: Start off by splitting the pile of 12 coins evenly into two piles, 6 in each pile. Put one pile on each side of the balance. The side that is weighed down has the fake coin it in. Ignore the other 6 coins.
Weighing #2: Now you have 6 coins left. Split the pile evenly again, 3 in each pile. Repeat the same process and put each pile on one side of the balance. The side that is weighed down has your fake coin in it. Ignore the other 3 coins.
Weighing #3: You have 3 coins left. Take two coins, whichever two you like, and weigh them. If they weigh the same, then the one you didn't weigh is the fake one. If one is heavier, then that heavier one is your fake coin.
Answer:
Beth can make 9 2 1/3 foot steps
Step-by-step explanation:
21/2.3=9.1
round to 9
Factor ouf 3x
3x(12x^2-5x-2)
factor
(3x)(3x-2)(4x+1)
Answer:
B. 252
Step-by-step explanation:
To find the answer, you have to use the formula to calculate the number of combinations as in this case, the order in which the objects are selected doesn't matter:
nCr=n!/r!(n-r)!
n= number of sample points: 10
r= number of sample points in each combination: 5
10C5= 10!/5!(10-5)!
10C5= 10!/5!*5!
10C5= 252
According to this, the answer is that you have 252 different ways to choose your school lunch.
