11 Plus Exams Forum

Hi can anyone pls tell me how to solve this question?

9(20)18 2(6)4 3( )18 ???

I don't know if it is easy and we are just overlooking something but just couldn't figure it out?

thanks

alberta wrote:Hi can anyone pls tell me how to solve this question?

9(20)18 2(6)4 3( )18 ???

I don't know if it is easy and we are just overlooking something but just couldn't figure it out?

thanks

Halve the second number, add the first, add 2 ?

18/2 + 9 +2 = 20

4/2 + 2 +2 = 6

18/2 + 3 +2 = 14


I would say a harder one as it involves a function (dividing second number) and adding a number not given, if that make sense.

Knowing the rules, trial and error on a piece of rough paper, or leaving it and re-visiting later sometimes works.

Hi thanks for that but just checked answer sheet and answer is 24! this one seems like it's going to be a division first but a tricky one!!!

Do you think answer incorrect on answer sheet as explaination above does seem like a valid one??

I think the answer sheet is wrong and Steve is right. If this is multiple choice, is 14 one of the answer options?

If you use a(b)c as the format of the numbers, then c/a + c gives you the given answer.

9(20)18 18/9 + 18 = 20

2(6)4 4/2 + 4 = 6

3(?)18 18/3 + 18 = 24


Edited due to baffling formatting issues!

I think I would have gone with TM's method

The majority of these questions can be answered by keeping to the following basic rules.

Middle number has been made using the numbers either side.
Same rule must apply for all 3 sets.
Sometimes 1 operation. Sometimes 2.
Second operation can be:

1] + - x / [divide sign!] the same number.
2] doubling/halving
3] + - x / [divide sign] the number on the left or right of the middle number.


9(20)18 2(6)4 3( )18 ???

Its the 3rd rule

18 divided by 9 = 2
2 add the number on the right of the middle number = 20

4 divided by 2 = 2
2 add the number on the right of the middle number = 6

18 divided by 3 = 6
6 add the number on the right of the middle number = 24



Patricia

Dearie me, a roast lunch with a glass of wine. and half term brain and I am good for nothing!

I shall climb back into my teapot ...

That was me last night with an Indian Take Away and a few glasses of wine...

P

Thank you everyone for all your replies!!

I am glad got to the bottom of it!! sally anne,no,14 wasn't on the answer sheet though that method made sense too!

I guess knowing the pattern now, the question seems easy but it def wasn't straight forward!!