Difference between revisions of "2011 AMC 8 Problems/Problem 8"

m
 
(4 intermediate revisions by 3 users not shown)
Line 1: Line 1:
 +
==Problem==
 
Bag A has three chips labeled 1, 3, and 5. Bag B has three chips labeled 2, 4, and 6. If one chip is drawn from each bag, how many different values are possible for the sum of the two numbers on the chips?
 
Bag A has three chips labeled 1, 3, and 5. Bag B has three chips labeled 2, 4, and 6. If one chip is drawn from each bag, how many different values are possible for the sum of the two numbers on the chips?
  
 
<math> \textbf{(A) }4 \qquad\textbf{(B) }5 \qquad\textbf{(C) }6 \qquad\textbf{(D) }7 \qquad\textbf{(E) }9 </math>
 
<math> \textbf{(A) }4 \qquad\textbf{(B) }5 \qquad\textbf{(C) }6 \qquad\textbf{(D) }7 \qquad\textbf{(E) }9 </math>
  
==Solution==
+
==Solution 1==
  
By adding a number from Bag A and a number from Bag B together, the values we can get are <math>3, 5, 7, 5, 7, 9, 7, 9, 11.</math> Therefore the number of different values is <math>\boxed{\textbf{(B)}\ 5}</math>. You can also approach this problem by noticing the sums will make odd multiples from <math>3</math> to <math>11</math> inclusive.
+
By adding a number from Bag A and a number from Bag B together, the values we can get are <math>3, 5, 7, 5, 7, 9, 7, 9, 11.</math> Therefore the number of different values is <math>\boxed{\textbf{(B)}\ 5}</math>.
 +
 
 +
==Solution 2==
 +
 
 +
The sum of an even number added to an odd number is always odd. The smallest possible sum is <math>3</math>, and the largest possible sum is <math>11</math>. The odd numbers in between can be achieved by replacing chips with <math>{\pm }2</math> within the same bag. Therefore, we can conclude that there are <math>(11-3)/2(*)+1=\boxed{\textbf{(B)}\ 5}</math> possible sums.
 +
 
 +
*Note that we are only accounting for odd numbers, thus the <math>/2</math>.
 +
 
 +
~megaboy6679
 +
 
 +
==Video Solution by WhyMath==
 +
https://youtu.be/qPLOGcNPdTQ
  
 
==See Also==
 
==See Also==
 
{{AMC8 box|year=2011|num-b=7|num-a=9}}
 
{{AMC8 box|year=2011|num-b=7|num-a=9}}
 +
{{MAA Notice}}

Latest revision as of 10:04, 18 November 2024

Problem

Bag A has three chips labeled 1, 3, and 5. Bag B has three chips labeled 2, 4, and 6. If one chip is drawn from each bag, how many different values are possible for the sum of the two numbers on the chips?

$\textbf{(A) }4 \qquad\textbf{(B) }5 \qquad\textbf{(C) }6 \qquad\textbf{(D) }7 \qquad\textbf{(E) }9$

Solution 1

By adding a number from Bag A and a number from Bag B together, the values we can get are $3, 5, 7, 5, 7, 9, 7, 9, 11.$ Therefore the number of different values is $\boxed{\textbf{(B)}\ 5}$.

Solution 2

The sum of an even number added to an odd number is always odd. The smallest possible sum is $3$, and the largest possible sum is $11$. The odd numbers in between can be achieved by replacing chips with ${\pm }2$ within the same bag. Therefore, we can conclude that there are $(11-3)/2(*)+1=\boxed{\textbf{(B)}\ 5}$ possible sums.

  • Note that we are only accounting for odd numbers, thus the $/2$.

~megaboy6679

Video Solution by WhyMath

https://youtu.be/qPLOGcNPdTQ

See Also

2011 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
Problem 7
Followed by
Problem 9
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. AMC logo.png