Maths homework showing working out

[Emochild]

xxx = 3024

I know the answer is

9x8x7x6=3024

But how the heck does dd show her working?

I thought it was a trial and error question but apparently not and her teacher has told her off previously for not showing working

-all numbers have to be less than 10

Can she break down 3024 into prime factors using the tree?

3024= 3x3x2x2x2x2x3x7 and then the prime factors multiply to get the numbers in the sum. Eg 9 is 3x3

Does the xxx stand for the digits?
She can find the prime factors first of 3024 using something like a prime factor tree then arrange as needed.

Sorry, that didn't display properly

?x?x?x?=3024

ok, once you have the prime factors then you just have to group them into 4 groups so that each multiple is 9 or less.

So a cherry tree thingy?

I'm so technical

in the morning, if no one else has done it I'll sketch it out and take a photo.

Thank you

The way dd worked it out was...

'I know 3000 and 24 are both in the 6 times table so that's my first number
3024/6=504
I know 504 is in the 4 times table and the 8 times table
504/8=63
7x9=63

So the numbers must be 6x8x7x9'

Works but long winded and not mathematical enough apparently

Odd, I'd consider that mathematical enough - though she could have started with I know that 3024 is divisible by 6 because it is an even number and the digits add to a multiple of 3.

here is how I'd do it.

Thank you

No doubt I shall be back next week for more help

Her working out is fine to show how she did it, I'd be happy with that.

What did she do wrong before?

The only thing I can think perhaps she was specifically told to relate it to the topic of prime factor decomposition.

Nope

No instructions other than what are the numbers

The same homework included compound interest and fractions with negative exponents

So a fun time was had all round!

She was previously told off for not showing her working when the question was

3 to the power of 25= ?

The teacher made her write

3x3x3x3x3...............

25 3s! Screw that for a laugh!

Mine might write 3 x 3 x 3 ..... X 3 with a small indication that the ... Means a total of 25 times.

That teacher really likes people showing their working.

Which is ironic because she gives questions like....

Give the value of (8/27)^-2/3

With no worked examples in their book or a text book to refer to!

3+0+2+4 = 9 so 3024 is divisible by 9

325 = 3535353535 = 243^5 = 847288609443

Emochild that's a grade A indices question.

Has to be done in 3 parts, I'd do 1/3 first (cube root) then 2 then ^-1 (flips the fraction) to get 9/4.

Thanks moo and OYBK

I'm guessing you are both maths teachers?

I'm toying with speaking to the school about it but they've recently removed the ability to contact specific departments -you have to email the info@school email and hope it gets through to the right person

Also don't want to piss the teacher off so she takes it out on dd