One number is 12 more than another....Find the larger number

[judyb]

One number is 12 more than another. The sum of the smaller number and twice the larger number is 39. Find the larger number.
A. 5
B. 7
C. 17
D. 34

Of course I said 34. :idea: Am I right?

 

[tkhunny]

You tell me. How did you arrive at that conclusion? Did you check or verify your results? Part of the learning of mathematics is the development of some confidence. Answer my questions and we can go from there.

 

[Denis]

Re: The largest number

One number is 12 more than another. The sum of the smaller number and twice the larger number is 39. Find the larger number.
A. 5
B. 7
C. 17
D. 34
Of course I said 34.Am I right?

What would you have "said" if there was no multiple choices ? :shock:

 

[judyb]

The largest number

Ok, originally I just said 34 because it is the largest number, but it was also 17 twice. 17 is 12 more than 5, but I'm confused again!

 

[jonboy]

Hi judyb!

One number is 12 more than another. The sum of the smaller number and twice the larger number is 39. Find the larger number.

A good way to solve these is setting up equations.

"One number is 12 more than another."

One number is \(\displaystyle x\) and the other (bigger) is \(\displaystyle x\,+\,12\)

"The sum of the smaller number and twice the larger number is 39."

\(\displaystyle \L x\,+\,2(x\,+12)\,=\,39\)

\(\displaystyle \L x\,+\,2x+24\,=\,39\)

\(\displaystyle \L 3x\,=\,15\)

\(\displaystyle \L x\,=\,5\)

"Find the larger number."

Can you finish?

 

[judyb]

The larger number

If x = 5 then 5 + 12 = 17. So 17 is the larger number.


I love your signature about math being like love. You need to know I don't do well with thar either! (LOL)