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The sum of Chris and Mike’s scores on a math quiz is 39. Mike’s score is twice the sum of Chris’ score and 3. Find each student’s quiz score.

User Attdona
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1 Answer

1 vote

Answer: c=11, m=28

Explanation:

c= Chris's score

m= Mike's score

c+m=39 we know from the equation that their scores

add up to 39, so this equation is a good starting

point.

c+2(c+3)=39 we also know that Mike's score is twice the sum of Chris's

score and 3 so we can substitute that in for his score.

now we can solve.

c+2c+6=39 distribute

3c+6=39 combine like terms

-6 -6

3c=33 addition property of equality

÷3 ÷3

c=11 multiplication property of equality

Now that we know Chris's score, we simply substitute that number in in our simple equation for earlier to find Mike's score.

11+m=39 substituted in 11 for c

-11 -11

m=28 addition property of equality

There you go! Don't worry, I had a lot of trouble with these types of problems too. That's why I'm so good at them now Hope this helps!

User XRavisher
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