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This question has baffled me, it has variables so I don't understand how i can get an outcome.

You Look

A jackpot of £1540 is to be shared equally amongst the winners.
If the number of winners is increased by 3 then the amount that each receives is reduced by £66. Find the number of winners.

I got the answer but only through trial and error and I still don't understand how you could get the answer.
Reply 1
Meat Loaf Rocks
This question has baffled me, it has variables so I don't understand how i can get an outcome.

You Look

A jackpot of £1540 is to be shared equally amongst the winners.
If the number of winners is increased by 3 then the amount that each receives is reduced by £66. Find the number of winners.

I got the answer but only through trial and error and I still don't understand how you could get the answer.


Let there be 'x' winners.
They normally win: 1540/x.
If the number of winners is increased by 3 they win: 1540/(x+3)
1540/(x+3)=1540/x - 66
Solve to find x.
Gaz031
Let there be 'x' winners.
They normally win: 1540/x.
If the number of winners is increased by 3 they win: 1540/(x+3)
1540/(x+3)=1540/x - 66
Solve to find x.


I have jsut tried that and got an answer of 67 which is incorrect it should be 7, found out through trial and improvement

can someone please confirm that I'm and idiot and can rearrange or that is the wrong expression to find x

cheers
Reply 3
1540/(x+3)=1540/x - 66
1540 = (1540/x - 66)(x+3)
1540 = 1540 + 4620/x - 66x - 198
198 = 4620/x - 66x
198x = 4620 - 66x2
198x + 66x2 - 4620 = 0
66x + 22x2 - 1540 = 0
x2+ 3x - 70 = 0

Now you just got to factorise that and i cant work it out at the moment. But if you put 7 into it you get 0 :smile:

PS. That might be a little long winded :/

Ok ive worked how to factorise.
x2+ 3x - 70 = 0
(x - 7)(x + 10) = 0
then you get x = 7 and x = -10 (you cant have -10 winners)
Reply 4
No it does work

You get:

66x^2 + 198x -4620=0 and then solve for x and only use the positive value of x