Algebra

[Guest]

I really need help , here is the problem:

Show three different methods fo solving the following problem: Find three consecutive counting numbers whose sum is 78. For each method demonstrate your use of Polya's four step method.

I already know that 25 + 26+ 27 = 78

 

[dtoepel]

If you represent the smallest of the numbers with "x", the next integer would be x + 1, and the next one ???

Setup an equation that adds these together and equals 78. Then solve the equation.

Dave

 

[Guest]

I understand that I think:

x+ represent's the 1st number
X + 1 = represent's the 2nd number
X + 2 = represent's the 3rd number

I'm still ost on showing three different methods for devising a plan for this problem and carrying out the plan using Polya's four-step method

 

[TchrWill]

78/4 = 19.5 making the 4 numbers 18, 19, 20 and 21.

 

[TchrWill]

OOPS - 78/3 = 26 making the 3 numbers 25, 26 and 27.

 

[Denis]

One of Polya's thing is: make a guess, then zoom in...

well, 30 is too high, so let's try 20:
20 + 21 + 22 = 63 ; nope
21 + 22 + 23 = 66 ; hey, goes up by 3!