Answer:
John weighs 375 pounds, and Karen weighs 125 pounds.
Step-by-step explanation:
The best way to solve this question is to assign the weights to variables.
Let's give variable <em>j</em> to John's weight and <em>k</em> to Karen's.
If John weighs 3 times as much as Karen, <em>j</em>=3<em>k</em>.
If 2x John's weight plus 1x Karen's weight = 875, then 2<em>j </em>+ <em>k </em>= 875,
which can also be written as 6<em>k</em> + <em>k</em> = 875<em> </em>since we established that <em>j</em>=3<em>k </em>and 2*3=6.
Now all we need to do to find <em>k</em> is solve the equation:
6<em>k</em> + <em>k</em> = 875 <em>combine common factors</em>
7<em>k</em> = 875 <em>divide both sides by 7</em>
<em>k</em> = 875/7
<em>k</em> = 125
Now that we know Karen's weight, we can find John's weight by using <em>j</em>=3<em>k</em>.
Plug the now known value of <em>k</em> in:
<em>j</em>=3<em>k</em>
<em>j</em>=3(125)
<em>j</em>=375
Now you have your pair:
<em>j</em>=375, <em>k</em> = 125.