Post a New Question

Math

posted by .

The sum of 3 numbers is 45. The first number is 4 times the second, while the third is 9 more than the second. Create an equation and solve.

  • Math -

    x = 2nd number

    4x + x + (x + 9) = 45

    6x + 9 = 45

    6x = 36

    x = 6

  • Math -

    x+y+z=45
    x=4y
    z=y+9

    4y+y+y+9=45
    6y=36
    y=6
    ...

  • Math -

    a = first number

    b = second number

    c = third number


    a = 4 b

    c = b + 9


    a + b + c = 45

    4 b + b + b + 9 = 45

    6 b + 9 = 45 Subtract 9 to both sides

    6 b + 9 - 9 = 45 - 9

    6 b = 36 Divide both sides by 6

    6 b / 6 = 36 / 6

    b = 6


    a = 4 b

    a = 4 * 6 = 24


    c = b + 9

    c = 6 + 9 = 15


    First numer 24 , second number 6 , third number 15


    a + b + c = 45

    24 + 6 + 15 = 45

    45 = 45

  • Math -

    thank you now i understand , i got the answer but i made a mistake on the equation

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

More Related Questions

Post a New Question