The main numbers and ratios or rates depending on the problem
It is 252. hope I helped!
Answer: Eleventh Grade
Step-by-step
The ratio of tenth graders to the school's total population is 86:255 = 33.7%.
The ratio of eleventh graders to the school's total population is 18:51 = 35.3%.
Since the probability of a student being in either tenth, eleventh, or twelfth grade = 1 = 100% (that is, certainty), then the probability of a randomly drawn student being in twelfth grade is (100-33.7-35.3)% = 31.0%.
When randomly choosing one student from the whole school, it is most likely (35.3%) that the student is in the eleventh grade.
Answer: 
Move all terms containing y to the left, all other terms to the right
<u>Add -14y to each side of the equation</u>
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<u>Combine like terms: 5y + -14y = -9y
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<u>Combine like terms: 14y + -14y = 0
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<u>Add '20' to each side of the equation</u>
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<u>Combine like terms: -20 + 20 = 0
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<u>Combine like terms: 7 + 20 = 27
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<u>Divide each side by -9</u>
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