Math question
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x(x+1)/2
Where X is the number of values
if you were to calculate 1+2+3+4+5+6+7+8+9+10 you would let x=10 so
10 (10+1) / 2
10x11 / 2
110 /2
=55
because you have added an extra 1 at the start stick that on at the end too.
I believe a famous physicist annoyed his teacher with tihs problem, I will try and remember the name and post details
edit: It was Gauss, supposedly the teacher set it as a punishment, working out 1+2+3...+99+100 and he wrote down 5050 and left it at that, Teacher couldn't figure out how he had done it so quickly and with no working. The idea is there are 50 groups that add up to 100 ie: 99+1, 98+2, 97+3 etc and 1 50 left over so 50x100 + 50 = 5050.
Where X is the number of values
if you were to calculate 1+2+3+4+5+6+7+8+9+10 you would let x=10 so
10 (10+1) / 2
10x11 / 2
110 /2
=55
because you have added an extra 1 at the start stick that on at the end too.
I believe a famous physicist annoyed his teacher with tihs problem, I will try and remember the name and post details
edit: It was Gauss, supposedly the teacher set it as a punishment, working out 1+2+3...+99+100 and he wrote down 5050 and left it at that, Teacher couldn't figure out how he had done it so quickly and with no working. The idea is there are 50 groups that add up to 100 ie: 99+1, 98+2, 97+3 etc and 1 50 left over so 50x100 + 50 = 5050.
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my local pub is doing an xmas raffle
there are 500 tickets numbered 1-500
I have been tasked to work out how much money will be raised and the split for the 4 prizes
if you buy a ticket you take a folded raffle ticket out of the tin
if you get number 30 then you pay 30p if you get 423 you pay £4.23
so as the resident amoeba I have been asked to work out what the total will be and how to split it
i am guessing over a grand but CBA to do the long hand way
thanks for any advice
LLL
there are 500 tickets numbered 1-500
I have been tasked to work out how much money will be raised and the split for the 4 prizes
if you buy a ticket you take a folded raffle ticket out of the tin
if you get number 30 then you pay 30p if you get 423 you pay £4.23
so as the resident amoeba I have been asked to work out what the total will be and how to split it
i am guessing over a grand but CBA to do the long hand way
thanks for any advice
LLL
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such a simple equation,makes life so easy
so Stewart what were you studying at uni?
i always wanted to be a physicist but as the eldest of 4 kids and my old man on the hod at the time I had to go straight to work at 16
thought about doing an OU degree but need 20 hours a week which I have not got
passed 7 o'levels at school,maths and english i did 2 years early then did statistics and english lit. for the last 2 years
about 5 years ago went to night school and passed a GCSE equivalent for spanish
and what was i doing today?
Laying 2 by 2's ,same as every day for the last 3 weeks :laugh: :laugh: :laugh:
LLL
so Stewart what were you studying at uni?
i always wanted to be a physicist but as the eldest of 4 kids and my old man on the hod at the time I had to go straight to work at 16
thought about doing an OU degree but need 20 hours a week which I have not got
passed 7 o'levels at school,maths and english i did 2 years early then did statistics and english lit. for the last 2 years
about 5 years ago went to night school and passed a GCSE equivalent for spanish
and what was i doing today?
Laying 2 by 2's ,same as every day for the last 3 weeks :laugh: :laugh: :laugh:
LLL
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I was the joker in the class! hated Maths and English and it shows everyday, but I've always been good with my hands (ask any valleys girls...!) and been grafting since I left school and I wouldn't change fook all in my life...I had 2 GCSE's art and science? I would have passed CDT but got kicked out for lobbing a prit stick at mr Thomas!
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