Answer:
Step-by-step explanation:
2005 AMC 8 Problems/Problem 20
Problem
Alice and Bob play a game involving a circle whose circumference is divided by 12 equally-spaced points. The points are numbered clockwise, from 1 to 12. Both start on point 12. Alice moves clockwise and Bob, counterclockwise. In a turn of the game, Alice moves 5 points clockwise and Bob moves 9 points counterclockwise. The game ends when they stop on the same point. How many turns will this take?
$\textbf{(A)}\ 6\qquad\textbf{(B)}\ 8\qquad\textbf{(C)}\ 12\qquad\textbf{(D)}\ 14\qquad\textbf{(E)}\ 24$
Solution
Alice moves $5k$ steps and Bob moves $9k$ steps, where $k$ is the turn they are on. Alice and Bob coincide when the number of steps they move collectively, $14k$, is a multiple of $12$. Since this number must be a multiple of $12$, as stated in the previous sentence, $14$ has a factor $2$, $k$ must have a factor of $6$. The smallest number of turns that is a multiple of $6$ is $\boxed{\textbf{(A)}\ 6}$.
See Also
2005 AMC 8 (Problems • Answer Key • Resources)
Preceded by
Problem 19 Followed by
Problem 21
1 • 2 • 3 • 4 • 5 • 6 • 7 • 8 • 9 • 10 • 11 • 12 • 13 • 14 • 15 • 16 • 17 • 18 • 19 • 20 • 21 • 22 • 23 • 24 • 25
All AJHSME/AMC 8 Problems and Solutions
The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions.
Answer:
21 1/3
Step-by-step explanation:
20 ÷ 15/16=
20/1 ÷ 15/16=
20/1*16/15=
4/1*16/3=
64/3=
21 1/3
Use formula: an = a1 * r^(n-1)
a1 = 2, r = -2
a12 = 2 * -2^(12-1)
a12 = 2 * -2^11
a12 = 2 * -2048
a12 = -4096
Solution: -4096
50-(30.8+4.9)=14.3 kg.
You start with 50 then you need to subtract 30.8 and 4.9 from it. So you add them together and get 35.7. Then you subract 25.9 from 50 and get 14.3 kg.
Answer:
3/7
Step-by-step explanation:
to find the ratio of the number of votes that weren’t mayor jackson you do 56-32. the ratio will be 24/56. now you just simplify to get 3/7