Mariana averaged 80 on her first three math exams. The first score was 86. The second score was 74. What was the third exam scor
1 answer:
The three scores are 86, 74, and an unknown score x. The average (i.e. the sum divided by how many there are) is 80, so we have
Multiply both sides by 3 and you get
Subtract 160 from both sides to get
Note: you could solve this exercise very quickly if you notice that the two numbers, 86 and 74, are symmetrical with respect to 80, which is the average. So, the third number must be the average.
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Hi there!
Let r be the number of matches that Rebecca's team won.
We know that Katheryn's team won 9 more matches than Rebecca's team, and we know that Katheryn's team won 52 matches.
Using this given information, we can create the following equation.
If you wish to solve this, we can subtract both sides by 9 to get the following value for r.
Have an awesome day! :)
~collinjun0827, Junior Moderator
Let r be the number of matches that Rebecca's team won.
We know that Katheryn's team won 9 more matches than Rebecca's team, and we know that Katheryn's team won 52 matches.
Using this given information, we can create the following equation.
If you wish to solve this, we can subtract both sides by 9 to get the following value for r.
Have an awesome day! :)
~collinjun0827, Junior Moderator
We apply our knowledge in variation.
The solution can be seen in the photo
