SOLUTION: write an inequality to find three consecutive numbers that sum a number fro 84 to 90

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Question 698992: write an inequality to find three consecutive numbers that sum a number fro 84 to 90
Answer by MathLover1(20850) About Me  (Show Source):
You can put this solution on YOUR website!

+84%3Cx+%2B+%28x+%2B1%29+%2B+%28x+%2B+2%29%3C90
+84%3Cx+%2B+x+%2B1+%2B+x+%2B+2%3C90
+84%3C3x+%2B+3%3C90
+84-3%3C3x+%2B+3-3%3C90-3
+81%3C3x%3C87
+81%2F3%3C3x%2F3%3C87%2F3
+27%3Cx%3C29....so, the first number is 28
then second number is 28%2B1=29 and third number is 28%2B2=30
let's check their sum
+84%3Cx+%2B+%28x+%2B1%29+%2B+%28x+%2B+2%29%3C90
+84%3C28+%2B+29+%2B+30%3C90
+84%3C87%3C90...it's true that their sum is a number greater than 84 and less than 90