Any secondary maths teachers around?

[SignOnTheWindow]

Really interested to know what level you would consider this question - KS3? GCSE? Seems a lot harder than the maths I flunked did at school:

The average monthly salary of m male employees and f female employees of a company is $2000. If the average monthly salary of the male employees is $(b + 200), find the average monthly salary of the female employees.

Aah sexism and misogyny ingrained within maths. How pleasant.

I'd refuse to answer it based on that alone.

@Molokonono

?

What does "b" represent? Are we assuming that there are equal numbers of male and female employees? Wouldn't the ratios of male to female affect the outcome?

This question is just emphasising how long it's been since I did any maths beyond basic arithmetic!!!

I mean, yes - obviously there's an implication that they'd be different, but I don't know because I can't answer the bloody thing!

Could we pretend for a moment that the wording is not men/women? Just for the purposes of answering my question about the maths itself?

Not enough information. What's the ratio of male to female employees? Is b = $2000?

@Mhw02

I know! I don't remember doing anything like this at school at all! Or maybe I was considered unable to cope with it. I was at secondary school in the 1990s.

@EllenJanesthickerknickers. I don't know. This is the question as it stands. Apparently there's no typo and it should be possible to work it out!

@SignOnTheWindow me too, secondary in the 1990s. I was good at maths (just haven't used it since!) I honestly think there's an error in the question, as EllenJane says, I don't think there's enough information given.

(Though someone cleverer than me will probably come along and say otherwise!)

Ok, apparently I've got this wrong - they're asking for the expression of this problem - not the answer. Ahem. sorry. As you were...

I'm such a dipstick!

Ok, average salary of (m+f) = 2000
Av Sal of m = b + 200
Av Sal of f = x
(b + 200 + x)/m+f = 2000
2000(m+f)= b+200+x
x = 2000(m+f) -b - 200

Maybe?

m+f = 2000
(b+200) + f = 2000
f = 2000-(b+200)
f = 1800-b

(Unless there's something about the averaging that I'm overlooking)

f is the number of female employees, not their salary, though, cantkeep.

Hmm, will think some more

Ah, no, realised that I've oversimplified.

Total salary = 2000(m+f)
Total salary for male employees = (b+200)xm
Total salary for female employees = y f where y = average female salary

2000(m+f) = (b+200)m +yf

2000(m+f) -(b+200)m = yf

2000m + 2000f - bm -200m = yf
[(1800 -b)m + 2000f] /f = y
y = (1800-b)m/f + 2000

??

Thank you both!

$(1800m - mb +2000 f)

f

The above is what DD got (the brackets are supposed to go round the line and the f as well, but I can't work out how to type it out that way).

I can't make head nor tale of it. Back to school for me . I think I'm going to visit Khan Academy tonight...

The maths syllabus has changed a lot since I was at school

TAIL not tail. FFS.

Oh, god...

2000 (m+f) = m(b+200) + fx
Ie total salary = )m(number of males plus number of females) multiplied by average salary which equals number of males multiplied by their average salary (b+200) plus number of females multiplied by their average salary (x)

Can you substitute now in the first equation?

Thart's the same as mine, just expressed in a slightly different way (I've collected the ms together and separated out the f part because the fs cancel). Whether it is right or not....

So it is. cross post

Well, if we all agree, it must be right .... maybe not!

Yes, (1800m +2000f -mb) / f

I can't get f to cancel out.

Is b the average female salary? That would make sense.

In which case you have the equation:

(m+f)2000= m(b+200) +fb
(m+f) 2000 = b(m+f) +200m
(m +f) (2000-b) = 200m

Rearranging quickly (so I may have made a mistake) I get:

b = 2000- 200m/(m+f)
=(1800m +2000f)/m+f (if you prefer it in that form)

I maybe wrong on my initial assumption (or the subsequent algebra)

Ellen, it won't cancel completely, but I split the overall fraction
[(1800-b)m +2000f] /f into twp parts. The first part remains over f:

(1800-b)m/f

The second part is 2000f/f so becomes 2000

hence y = (1800-b)m/f + 2000

I getcha. Not sure which looks more elegant.