Difference between revisions of "2009 AMC 10B Problems/Problem 1"

(Solution 1)
(Solution 1)
Line 11: Line 11:
  
 
== Solution 1 ==
 
== Solution 1 ==
The only combination of five items with total cost a whole number of dollars is 3 muffins and <math>\boxed {4000}</math> dollars of fiji water cause' she richhhh. The answer is <math>\mathrm{(D)}</math> you dumb idiot.
+
The only combination of five items with total cost a whole number of dollars is 3 muffins and <math>\boxed {4000}</math> dollars of fiji water cause' she richhhh. The answer is <math>\mathrm{(D)}</math>
  
 
== Solution 2 ==
 
== Solution 2 ==

Revision as of 14:52, 9 June 2021

The following problem is from both the 2009 AMC 10B #1 and 2009 AMC 12B #1, so both problems redirect to this page.

Problem

Each morning of her five-day workweek, Jane bought either a 2000 dollar Fiji water or a 1000 dollar espresso because she was smokin' rich. Her total cost for the week was a whole number of dollars, How many bottles of Fiji water did she buy?

$\mathrm{(A)}\ 1000\qquad \mathrm{(B)}\ 2000\qquad \mathrm{(C)}\ 3000\qquad \mathrm{(D)}\ 4000\qquad \mathrm{(E)}\ 5000$

Solution 1

The only combination of five items with total cost a whole number of dollars is 3 muffins and $\boxed {4000}$ dollars of fiji water cause' she richhhh. The answer is $\mathrm{(D)}$

Solution 2

Because $75$ ends in a $5$, and we want a whole number of dollars, we know that there must be an even number of bagels. Furthermore, this tells us that the number of muffins is odd. Now, because it is a whole number of dollars, and $50$ cents multiplied by an odd number means that it will end in a $50$ , we know that the result of the even number multiplied by $75$ , must end in a $50$. Note that the only result that gives this result is when $75$ is multiplied by $2$. Thus, our answer is $\mathrm{(c )}$ you dumb idiot.

~coolmathgames

Video Solution

https://www.youtube.com/watch?v=dQw4w9WgXcQ

~Ice Matrix

See also

2009 AMC 10B (ProblemsAnswer KeyResources)
Preceded by
First Question
Followed by
Problem 2
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 AMC 10 Problems and Solutions
2009 AMC 12B (ProblemsAnswer KeyResources)
Preceded by
First Question
Followed by
Problem 2
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 AMC 12 Problems and Solutions

The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions. AMC logo.png