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The sum of the reciprocals of two consecutive even integers is 9/40. Find the integers. smaller integer larger integer

User Prabeesh
by
8.0k points

2 Answers

1 vote

Answer:

Smaller integer is 8, larger one is 10.

Explanation:

Let one integer be x then the other is x+2, so from the given information:

1 /x + 1 / x+2 = 9/40

Multiply through by 40x(x+2);

40(x + 2) + 40x = 9x(x + 2)

80x + 80 = 9x^2 + 18x

9x^2 - 62x - 80 = 0

(9x + 10)(x - 8) = 0

x = 8, -1.1111

x must be 8 so the other one is 8+2 = 10.

User Wiz
by
8.3k points
6 votes

Answer:

8 and 10

Explanation:

2x and 2x+2 the integers

  • 1/2x+1/(2x+2)= 9/40
  • 1/x+1/(x+1)=9/20
  • (x+x+1)/(x*(x+1))= 9/20
  • 9x²+9x= 20(2x+1)
  • 9x²-31x-20=0
  • x= 4 integer solution

So the numbers are 8 and 10

User Mostafa Gazar
by
7.7k points

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