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QUESTION 27c

3 raffles - 100 tickets each

MARY: 2/100 = 1/50 = 0.02 <B>(1 mark)</B>

JANE:
Propability of winning both ticks is 1/100 x 1/100 = 1/10,000 <B>(1 mark)</B>
Probabilty of winning first draw but not the second = 1/100 x 99/100 = 99/10,000
Propability of winning second but not first = 99/100 x 1/100 = 99/10,000

CONCLUSION...
Propability of winning AT LEAST 1 (is the sum of the above 3 calculations)
1/10 000 plus 99/10 000 plus 99/10 000 = 199/10 000 = 0.0199 <B>(1 mark)</B>

Hence, mary has a slightly beter chance... <B>(1 mark)</B>
Yeah I got that just then. But i said equal in the test. FML!!!!!! In the test i thought i might be wrong seeing how it was worth 4 marks but I didn't have enough time to come back to it. I'll probably only get 2/4 max. FML!
 

I Study Hard

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26 (c) i. $2200 x 12 x 20 = $528,000
Its a reducing balance loan, so the compound interest formula wouldn't have worked because it wouldn't have taken into account the repayments she was making, so the interest wouldn't have come out right. The total was the repayments she was making multiplied by 12 to get how much she paid in a year and then multiplied by 20 to get the full amount. (i'm pretty sure thats right)

26 (c)ii. 300000 = M {(1 + (0.06/12))^240 - 1
-----------------------------
(0.06/12) (1 + (0.06/12)^240}

And then you work it out from there, and i think the calculated monthly repayment was slightly off what the bank was making her pay but not by very much
 

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26 (c) i. $2200 x 12 x 20 = $528,000
Its a reducing balance loan, so the compound interest formula wouldn't have worked because it wouldn't have taken into account the repayments she was making, so the interest wouldn't have come out right. The total was the repayments she was making multiplied by 12 to get how much she paid in a year and then multiplied by 20 to get the full amount. (i'm pretty sure thats right)

26 (c)ii. 300000 = M {(1 + (0.06/12))^240 - 1
-----------------------------
(0.06/12) (1 + (0.06/12)^240}

And then you work it out from there, and i think the calculated monthly repayment was slightly off what the bank was making her pay but not by very much
I put 240 times by 2200 but its wroong dude
 

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OMG guys i just realised i completely read that dice question wrong X_X
 

cmanassa

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There was a 6/36 chance of getting a difference of 0, 10/36 for 1, 8/36 for 2, 6/36 for 3, 4/36 for 4, 2/36 for 5. You just multiply these chances with 18 to get the difference they should theoretically show. So experiment two was more correct..
Good stuff! Then u did relative frequencies of experiment 1 and 2... and compared which were closer to thge theoretical propabilities?

experiment 1: (for 0-5) 3/18 3/18 2/18, 4/18, 3/18, 3/18
0.17 0.17 0.11 0.22 0.17 0.17
experiemtn 2: (for 0-5) 4/18 4/18 3/18 3/18 2/18 2/18
0.22 0.22 0.17 0.17 0.11 0.11
theoreticals: for 0-5 6/36 10/36 8/36 6/36 4/36 2/36
0.16 0.27 0.22 0.16 0.11 0.055

As can be seen, the experments relative frequencies were closer to the theoretical propabilities calculated
 
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QUESTION 27c

3 raffles - 100 tickets each

MARY: 2/100 = 1/50 = 0.02 <B>(1 mark)</B>

JANE:
Propability of winning both ticks is 1/100 x 1/100 = 1/10,000 <B>(1 mark)</B>
Probabilty of winning first draw but not the second = 1/100 x 99/100 = 99/10,000
Propability of winning second but not first = 99/100 x 1/100 = 99/10,000

CONCLUSION...
Propability of winning AT LEAST 1 (is the sum of the above 3 calculations)
1/10 000 plus 99/10 000 plus 99/10 000 = 199/10 000 = 0.0199 <B>(1 mark)</B>

Hence, mary has a slightly beter chance... <B>(1 mark)</B>
HAHA thats whats i got but i stuffed up. i forgot to add Mary's 2nd raffle in and had her as 0.1 instead of 0.2, so i said Jane was better but all the the calcualtions wright. ill prob just get 1 mark taken off for not wirting it down the bottom right. DAMMIT i've probably stuffed that paper up so much. it was easy but i forgot everything so i had to learn in the exam how to do things again (i jsut can't study haha)
 
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whatg people get for this rhys has forgotten his 4-digit number , he konws first on is either 5 or 6 ?
 

LauraP12

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wasn't 23) b) ii) 1/2 x 1/10 x 1/10 x 1/10? cause he has a 1 in 2 chance of picking 5 or 6 which is correct and then a 1 in 10 chance of picking each number after that correctly.
 

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