The sum of two number is 15. twice one number equals 3 times the other. Find the numbers?

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  • 4 weeks ago

    Let the numbers be x and y.

    x + y = 15

    2 * x = 3 * y

    x = 1.5 * y

    Use this for x in the first equation.

    1.5 * y + y = 15

    2.5 * y = 15

    y = 6

    x + y = 15

    x = 9

    Check:

    2 * 9 = 3 * 6

    18 = 18

    I hope this is helpful for you.

  • 4 weeks ago

    Let x and y be the two numbers. 

    x + y = 15 

    2x + 2y = 30 

    2x - 3y = 0 

    5y = 30 

    y = 6 

    x = 9 

    The two numbers are 6 and 9.

  • mizoo
    Lv 7
    4 weeks ago

    Let the numbers a and b.

    2a = 3b => a = (3/2)b

    a + b = 15

    (3/2)b + b = 15

    (5/2) b = 15

    b = 15 * 2/5

    b = 6

    a + b = 15 => a + 6 = 15

    a = 9

    The numbers are 6 and 15.

    • mizoo
      Lv 7
      4 weeks agoReport

      Yes, sure. Thanks for correcting me.

  • 4 weeks ago

    x+ y = 15

    2x = 3y

    so

    2x + 2y = 30

    ==> 3y + 2y = 30

    ==> 5y = 30

    ==> y = 6

    hence x = 9

    2*9 = 18

    3*6 = 18

    so 2*9 = 3*6

    so the numbers are 6 and 9

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  • 4 weeks ago

    6,9

    ................

  • 4 weeks ago

    9 and 6.

    Start with 8 and 7. They are not it. Add one to the 8, subtract 1 from the 7. Bingo!

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