Difference between revisions of "2007 iTest Problems/Problem 26"

(Created page with "== Problem == Julie runs a website where she sells university themed clothing. On Monday, she sells thirteen Stanford sweatshirts and nine Harvard sweatshirts for a total of &#0...")
 
(Solution to Problem 26)
 
Line 3: Line 3:
 
Julie runs a website where she sells university themed clothing. On Monday, she sells thirteen Stanford sweatshirts and nine Harvard sweatshirts for a total of $370. On Tuesday, she sells nine Stanford sweatshirts and two Harvard sweatshirts for a total of $180. On Wednesday, she sells twelve Stanford sweatshirts and six Harvard sweatshirts. If Julie didn't change the prices of any items all week, how much money did she take in (total number of dollars) from the sale of Stanford and Harvard sweatshirts on Wednesday?  
 
Julie runs a website where she sells university themed clothing. On Monday, she sells thirteen Stanford sweatshirts and nine Harvard sweatshirts for a total of $370. On Tuesday, she sells nine Stanford sweatshirts and two Harvard sweatshirts for a total of $180. On Wednesday, she sells twelve Stanford sweatshirts and six Harvard sweatshirts. If Julie didn't change the prices of any items all week, how much money did she take in (total number of dollars) from the sale of Stanford and Harvard sweatshirts on Wednesday?  
  
== Solution ==
+
 
 +
==Solution==
 +
 
 +
Let <math>s</math> be cost of Stanford clothing, and let <math>h</math> be cost of Harvard clothing.  From the given information,
 +
<cmath>13s + 9h = 370</cmath>
 +
<cmath>9s + 2h = 180</cmath>
 +
Add the two equations to get
 +
<cmath>22s + 11h = 550</cmath>
 +
Multiply both sides by <math>\frac{6}{11}</math> to get
 +
<cmath>12s + 6h = 300</cmath>
 +
Thus, Julie earns <math>\boxed{\$300}</math> on Wednesday.
 +
 
 +
==See Also==
 +
{{iTest box|year=2007|num-b=25|num-a=27}}
 +
 
 +
[[Category:Introductory Algebra Problems]]

Latest revision as of 19:12, 10 June 2018

Problem

Julie runs a website where she sells university themed clothing. On Monday, she sells thirteen Stanford sweatshirts and nine Harvard sweatshirts for a total of $370. On Tuesday, she sells nine Stanford sweatshirts and two Harvard sweatshirts for a total of $180. On Wednesday, she sells twelve Stanford sweatshirts and six Harvard sweatshirts. If Julie didn't change the prices of any items all week, how much money did she take in (total number of dollars) from the sale of Stanford and Harvard sweatshirts on Wednesday?


Solution

Let $s$ be cost of Stanford clothing, and let $h$ be cost of Harvard clothing. From the given information, \[13s + 9h = 370\] \[9s + 2h = 180\] Add the two equations to get \[22s + 11h = 550\] Multiply both sides by $\frac{6}{11}$ to get \[12s + 6h = 300\] Thus, Julie earns $\boxed{$300}$ on Wednesday.

See Also

2007 iTest (Problems, Answer Key)
Preceded by:
Problem 25
Followed by:
Problem 27
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 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 TB1 TB2 TB3 TB4