# Year 8 question - finding the pattern of numbers in a grid

• Apr 10th 2009, 12:34 AM
jonomantran
Year 8 question - finding the pattern of numbers in a grid
I really need help with this maths question. It is basically asking to find the unknown number. This is a year 8 question but for some reason it is extremely hard for me to figure out, I even tried asking some of my friends but they do not know. Here is an attached picture of the question. The answer is in the back of the book which is 32 but i don't know why. Please help!(Doh)
• Apr 10th 2009, 01:09 AM
janvdl
Quote:

Originally Posted by jonomantran
I REALLY NEED HELP WITH THIS MATHS QUESTION. It is basically asking to find the unknown number. This is a year 8 question but for some reason it is extremely hard for me to figure out, I even tried asking some of my friends but they do not know. Here is an attached picture of the question. The answer is in the back of the book which is 32 but i don't know why. Please help!(Doh)

Okay, I've spotted it.

Let $\displaystyle x$ be the left-most column value of the row $\displaystyle n$, and let $\displaystyle y$ be the middle column value of row $\displaystyle n$.

Then:

$\displaystyle x = (y \times n) + (2 \times n)$

Let's focus on some of the rows:

$\displaystyle 6 = ((4 \times 1_{(the \ row \ number)}) + 2)$

$\displaystyle 20 = ((8 \times 2_{(the \ row \ number)}) + 4)$

$\displaystyle 12 = ((2 \times 3_{(the \ row \ number)}) + 6)$

$\displaystyle ? = ((6 \times 4) + 8) = 32$
• Apr 11th 2009, 07:16 AM
jonomantran
One word - GENIUS and btw do u rekon this is year 8 level?
• Apr 11th 2009, 09:01 AM
TKHunny
In Year 9 you should learn that there are infintely many solutions. I'll allow that this is substantially more complicated than your basic pattern recognition busy work, but it is still just a finite list of values.