Maths test - to think Civil Service have it wrong?

[Sharingaroomtinightthen]

I’ve just applied for a Civil Service test. Part of it is passing a numerical test.

This is the question.

The answer is 125%. I’m sure of it.

If you start with £100, and in the first year it doubles it’s £200. So at the of year one it’s £200.

In year two it trebles to £600.

It then falls by a quarter in the third year to £450.

So end of year 1 - £200.

End of year 3 - £450.

It’s increased by 125%.

125% isn’t an answer option.

WIBU to email and tell them they’ve got it wrong?

@DeftShaker

I get that the maths graduate used 100 as a base for explanation. Thus I understand this to represent 50 as 50%.

100 doubles to 200 then triples to 600 then decreased by 25% to 450.

The difference between end of year 1 and year 2 is 250 (450-200) which I calculate as 450%.

In my mind you add up the 5 (250/50=5) 50% together to get to the 450%. I know this is random and doesn’t make sense to so many on here just how my brain works.

The answer to me given the options on the drop down is therefore 450%

Everyone thinks I am stupid on here which is fine it’s anonymous but at least my brain has been engaged this morning right or wrongly!

I am sticking with the maths graduate who also got 450%.

The option is leave the answer blank because 125% is not an option. In my mind 450% fits.

Just out of interest, what answer did you select?
Did it tell you you got that specific question wrong?

You remain wrong. See my pp on ambiguity

Oh, and so on, until 125% increase brings us to 450.

Then I remain wrong happily. But if the increase isn't a difference between the two numbers, what is it?

increase is the difference between two numbers.

percentage increase is the difference between the numbers compared with the starting number, times 100.

percentage increase = (new-original)/original x 100%

If you increase 200 by 100% what do you get?

The ‘maths graduate’ is wrong, twice over.

A random one, can’t remember. No, it didn’t give individual answers.

The difference between end of year 1 and year 2 is 250 (450-200) which I calculate as 450%.
The increase from 200 to 450 is 250.

Which is a 125% increase.

Put it this way: A 100% increase of 200 would be 200 (for a total of 400) - right?

a 450% increase would be 900.

You have been correct throughout.

How the actual fuck is this still going? @Sharingaroomtinightthen how have you got this much patience?

Absolutely; the psychology is fascinating. Some people clearly find it very easy to bluster on all sorts of topics and there's no clear correlation between level of confidence and level of accuracy/knowledge.

Plus the attitude towards maths itself is interesting. "Oh, I don't know! That's just what my silly brain tells me to do!" Or, "It makes no sense, but 105% of three hamsters is actually a zebra. Maths is insane!" Etc.

This question isn't integral calculus or string theory; it's pre-GCSE level maths. Arithmetic. Doesn't even require algebra, just some pretty basic reasoning.

I see what you are saying here but in my mind using 100 as a base only simplifies the equation and allows you to use multiples of 50 as a representative of 50%. That is why 250 difference in this mathematical equation represents a 450% increase.

The only answer I would pick on the drop down is 450%.

In my view the question is not just about percentages. It is more complicated.

As I said Grade C in GCSE maths 35 years ago!

I agree it is in the wording too but if you use the base circulation you can at least get an answer from the drop down that fits. 450% 😂

The increase is how much it’s gone up by.

If I weighed 100kg and I wanted to lose 25% of my body weight then I’d be aiming for 75kg. If I wanted to gain 25% of my body weight I’d be aiming for 125kg. The increase in my bdoyweight is 25%

If ended up weighing 225kg then I’ve gained 125% of my body weight. The increase is 125%.

125%.

No, you've been wrong throughout.

It's a 125% increase. It is not complicated or ambiguous.

Yes, she knows this, she has said it several times. Unfortunately people keep disagreeing with her.

Wtf 😬

The question contains no ambiguity for anyone with a basic grasp of English, maths and the workings of percentages. There’s only one correct answer, which is 125%

It’s so interesting. I wonder what would have happened if the OP had left the answers off and just asked people what they thought the answer was? I bet a lot more people would have said 125%.

This thread is an object lesson in how our education has failed so so many in basic numeracy and literacy.

The question is worded very clearly, the maths is below GCSE level.

Yet in the face of very clear explanations, links, screenshots, people being wedded to their incorrect answers (anything but 125%) is actually upsetting.

How were you able to screen print the question? If anyone can do this, then what is the point of the test as surely lots of people must know the questions beforehand if they know someone who has taken the test?

I agree. I think there are a number of posters who cannot fathom the question is incorrect.

Sorry I was replying to the person who asked me to explain my post, not to the OP.

Well all I’ve got is O Level Maths a very long time ago!