# year 10 maths need help

basically this is going to be a string of questions that I have to revise for year 11 I wouln't like the answers unlesss you can like explain it to me that would be great thanks xx

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Original post by kai130305
basically this is going to be a string of questions that I have to revise for year 11 I wouln't like the answers unlesss you can like explain it to me that would be great thanks xx

shoot. Or you can hmu and send me questions on snapchat and I can help you out. Im bored
30 students in a class sat a mathematics test
the mean mark in the test for 30 students was 26.8
13 of the students in the class are boys the mean mark in the test for the boys was 25
find the mean mark for the girls
Original post by ClayJensen817
shoot. Or you can hmu and send me questions on snapchat and I can help you out. Im bored

I don't have snap sorry I have a brick phone (strict parents) but I would love your help xx
Original post by kai130305
I don't have snap sorry I have a brick phone (strict parents) but I would love your help xx

Original post by ClayJensen817

okay x
Original post by kai130305
30 students in a class sat a mathematics test
the mean mark in the test for 30 students was 26.8
13 of the students in the class are boys the mean mark in the test for the boys was 25
find the mean mark for the girls

Okay so the formula for mean is: total marks/number of students

Okay?

so if we use that then total marks/30 = 26.8

And there are 13 boys and 17 girls.

so total marks for boys+ total marks for girls = total marks

So total marks for boys/13 = 25

so total marks for boys = 13×25= 325

Total marks for class= 30×26.8= 804

804-325= 479 which is the total marks for girls

so mean marks for girls is 479/17 = 28.2

Okay?
Original post by ClayJensen817
Okay so the formula for mean is: total marks/number of students

Okay?

so if we use that then total marks/30 = 26.8

And there are 13 boys and 17 girls.

so total marks for boys+ total marks for girls = total marks

So total marks for boys/13 = 25

so total marks for boys = 13×25= 325

Total marks for class= 30×26.8= 804

804-325= 479 which is the total marks for girls

so mean marks for girls is 479/17 = 28.2

Okay?

you make so much more sense than my teacher thank you so its just like reversing the mean? to get the answer?
(edited 4 years ago)
Original post by kai130305
you make so much more sense than my teacher thank you so its just like reversing the mean? to get the answer?

Exactly...

and Omggggg someone told me that when I was teaching her GCSE Physics last week. YOU MADE MY DAY!!!!

OMGGGG THANK YOUUUUUU!!!!! HAHAHHAHA

I SOOOOOOOO WANNA BE A TEACHER LMAO
Original post by ClayJensen817
Exactly...

and Omggggg someone told me that when I was teaching her GCSE Physics last week. YOU MADE MY DAY!!!!

OMGGGG THANK YOUUUUUU!!!!! HAHAHHAHA

I SOOOOOOOO WANNA BE A TEACHER LMAO

well your good at it xx
use algebra to show that the reoccurring decimal 0.345 is 19/55
the dots are on top of the 45 and the last bit is supposed to be a fraction x
(edited 4 years ago)
Original post by kai130305
well your good at it xx

hahhahahahahah

(smiles a lot)

Thank you ehem...

Original post by kai130305
use algebra to show that the reoccurring decimal 0.345 is 19/55
the dots are on top of the 45 and the last bit is supposed to be a fraction xx

So you use the bus stop method if you have heard of it?

19÷55
Original post by ClayJensen817
So you use the bus stop method if you have heard of it?

19÷55

is not divide I don't think so anyway I just don't know how to put one on top of the other on this
Original post by kai130305
is not divide I don't think so anyway I just don't know how to put one on top of the other on this

In all honesty I forgot this method haha. Im doing A levels lmao
Original post by ClayJensen817
In all honesty I forgot this method haha. Im doing A levels lmao

wait is is that like that is the answer but I have to use algebra to show that??? x
Original post by kai130305
wait is is that like that is the answer but I have to use algebra to show that??? x

By algebra they mean the division method. look it up
Original post by ClayJensen817
By algebra they mean the division method. look it up

ohhhhh okay thanks x
prove that the sum of squares of any three consecutive odd numbers is always 11 more than a multiple of 12 xx
Original post by kai130305
30 students in a class sat a mathematics test the mean mark in the test for 30 students was 26.813 of the students in the class are boys the mean mark in the test for the boys was 25find the mean mark for the girls give your answer to 3 sig fig xx
So basically all you gotta do is to find the sum of boys by multiplying the mean with their frequency which is equal to 804 and this is the total n of students then multiply 25*13 to find n of boys after then subtract 804 with 325 to get the sum of girls = 479 divide it by the n if girls which is 17 ans gonna be 28.176 ~~ 28.2 Hope you got it😊