120, 60, 80, 90, ??

[KeiwaM]

So at my Military Session today, I was posed with this question to which I could not find an answer. It is really bugging me, so if you can, please let me know.

The following numbers all have a correlation in the order they are posed. Calculate the last number.

120 - 60 - 80 - 90 - ___

REMEMBER, ALL NUMBERS HAVE A CORRELATION IN THIS EXACT ORDER

 

[Spoon]

@TinySlayer

 

[Aquaa]

@TinySlayer mathematician help him out

 

[Mage]

120 x n-1/n

Next is 96

 

[Lelios1]

150?

the one above me seems more reasonable

 

[money]

With some rather simple math, i get this:


∑n=1∞n3(132+103+32√+64+2x52+2x132103+32√√2242)n=42∑n=1∞n3(132+103+32+64+2x52+2x132103+322242)n=42

 

[KeiwaM]

Okay my friend

With some rather simple math, i get this:


∑n=1∞n3(132+103+32√+64+2∗52+2∗132103+32√√2242)n=42∑n=1∞n3(132+103+32+64+2∗52+2∗132103+322242)n=42

What the fuck does this mean and how does 42 correlate to the order of numbers

 

[Eviction Notice]

With some rather simple math, i get this:


∑n=1∞n3(132+103+32√+64+2x52+2x132103+32√√2242)n=42∑n=1∞n3(132+103+32+64+2x52+2x132103+322242)n=42

>simple math

alright Einstein, calm down

 

[money]

Yo

Okay my friend


What the fuck does this mean and how does 42 correlate to the order of numbers

Everything I did seems correct, can you tell me what I did wrong???
The 42 is, with this math and 4 first numbers, the answer.
Ask me what you need explained I just double checked and it seems ok...

 

[KeiwaM]

Yo


Everything I did seems correct, can you tell me what I did wrong???
The 42 is, with this math and 4 first numbers, the answer.
Ask me what you need explained I just double checked and it seems ok...

I'm not saying you did anything wrong, I'm just saying I'm a knob and didn't understand any of it lol

It wasn't a math test but a logic thinking test. There is a corelation between these numbers logically speaking which you would be able to calculate in your head. Not that Stephen Hawking Equasion there

 

[money]

There is a corelation between these numbers logically speaking which you would be able to calculate in your head. Not that Stephen Hawking Equasion there

Pretty sure anyone can solve this in their heads in a minute or two...

 

[KeiwaM]

Pretty sure anyone can solve this in their heads in a minute or two...

I didn't even know what half of those things a re, and I graduated Primary school. This isn't standard maths, that's fucking College or University level maths.

 

[KeiwaM]

Alright.

My friend Ymi thought about this a littlebit and came up with this solution:

You take 120 (First Number) as the base

Remove 1/2 from 120 and you have 60

Remove 1/3 from 120 and you have 80

Remove 1/4 from 120 and you have 90

Remove 1/5 from 120 and you have 96

96 is the answer.. I think

 

[Sagittarius]

I think it's 100.
You can have a row of numbers/fractions you multiply 120 with.
1 - 1/2 - 2/3 - 3/4 - 4/5 - 5/6
The reason it jumps from 1 to 1/2 is because you connect the numbers with a dash
So 120 *1 = 120, 120 * 1/2 = 60, 120 * 2/3 = 80, 120 * 3/4 = 90, 120 * 5/6 = 100, etc.

120 x n-1/n

Next is 96

Wouldn't the first one be zero then, since (1-1)/1 = 0?

 

[Creepis]

Seems like you werent the only one who got this at a military session https://math.stackexchange.com/questions/2104450/120-60-80-90

The order/sequence itself is too short to even make out to continue it if my 1 IQ brainlet is right as I forgot most of all maths formulas from secondary school aswell as job college to even calculate anything out of this. You either have to pick a natural or a creative answer, IMO it would be 120, 60, 80, 90, 180, 90, 110, 120, 240 (multiply 90 by 2, half it by 2, add +20, add +10, multiply by 2, half it by 2 etc.). Anything would be possible as long as the math checks out.

If not then ignore my retarded answer.

 

[John Daymon]

- 110 easy.

 

[Yaseen]

the answer is 4 as Big Shaq said

 

[Samジ]

@TinySlayer

 

[TinySlayer]

It's a terrible question unless you've missed out a key part of the question. There are multiple perfectly valid answers, mostly listed on the stack exchange post @Creepis linked.

Most obvious option is that fraction thing though: a_0=120, a_n = a_0(n/(n+1)) where n>1.

 

[JackHilton123]

It's a terrible question unless you've missed out a key part of the question. There are multiple perfectly valid answers, mostly listed on the stack exchange post @Creepis linked.

Most obvious option is that fraction thing though: a_0=120, a_n = a_0(n/(n+1)) where n>1.

ima just agree to what you say cause i aint got a fucking clue