Question 1093358: A book opened to two pages with a product of 7140 what are the facing pages Found 4 solutions by josmiceli, MathTherapy, greenestamps, richwmiller:Answer by josmiceli(19441) (Show Source): You can put this solution on YOUR website! Let the facing pages be and
given:
complete the square
Take the square root of both sides
and
The facing pages are 84 and 85
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check:
OK Answer by MathTherapy(10551) (Show Source): You can put this solution on YOUR website!
A book opened to two pages with a product of 7140 what are the facing pages
Since the pages are consecutive numbers, we just need to take the square root of 7,140, which is 84.4985207.
This number is BETWEEN the 2 numbers we're seeking. Therefore, page numbers are:
That's ALL!
Answer by greenestamps(13198) (Show Source): You can put this solution on YOUR website! Instead of the ugly algebra in the first response you got, and without having to find the square root of 7140 as in the second response, try doing some estimating and logical reasoning.
80*80= 6400; 90*90 = 8100.
So the two page numbers must be between 80 and 90.
The product of the two page numbers must is 7140, which ends in "0", so one of the two page numbers must be 85.
Then you can either try the two possible answers of 84 and 85, or 85 and 86; or you can notice that 7140 is quite a bit closer to 6400 than it is to 8100, so the more likely answer is 84 and 85.
And trying that works.... Answer by richwmiller(17219) (Show Source): You can put this solution on YOUR website! As ugly as the algebra solution appears, this website is called algebra.com and most students with problems are studying algebra. And as elegant as thinking and logic are compared to ugly algebra, most teachers will want an algebraic solution.