sc math help..a few questions from a practice book (1 Viewer)

Riot09

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10.sam earns $720/week.he saves $160,spends $180 on rent,$240 on living expenses and $140 on entertainment.he makes apie chart to show his expenses.the size of the entertainment angle would will be:
13.jamie adds his marks for his 6 exams.he has a median ogf 60.calculate the missing number.
50,54,58,x,62,68
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14.josselyn earns $400 a week.she spends $280.calculate the percentage of her pay that is left.
22.molly looks at her 5 exam marks.she has an average of 75%.she finds that if she arranges them in order there is always a difference of 3% between one mark and the next.what are the 5 marks?
33.jim bought a box of cd’s for $45.they had been reduced by 10%.this means they were originally marked
a.$50 b.49.50 c.$40.50 d.$4.50
48.debra borrows $1500 for 3 years.interest is charged at $75 per month.how much will she pay back in total?
a.$900 b.$2,700 c.$15,900 d.$17,700
thanx in advance
 

salih08

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normally by the time i answer someone else has lol.

anyway the first one is quite easy.

circle is 360 degrees from the centre. 720 is twice 360. so all u do is half everything to get it to the right aount (ie 1/2 = 2/4, 140/720=70/360.

so expenses would be 70 degrees out of 360 degrees of the circle. ( i think)

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the 2nd one:
there is an even amount of scores so the average of the middle 2 will give u the median (middle number).
the middle 2 are 58 and x

so x+58 / 2 = 60

*2 on both sides

x+58=120

-58 from both sides

x= 62.

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14.
400-280=120 (is left)
120/400*100 = 30% left.

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start from 75. deduct 3 (get a score), deduct 3 (get another score), start from 75. add 3, get a score, add another 3, get a score.
now u have 5 scores with an average of 75.
this 69,72,75,78,81 (all %)
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10% of 50 is 5 . so 45 = 50-45 . answer is a.

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75 dollars each month. 3 years = 36 months/
total interest = 75 x 36 = $2700


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home this is useful
 
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supre

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10.sam earns $720/week.he saves $160,spends $180 on rent,$240 on living expenses and $140 on entertainment.he makes apie chart to show his expenses.the size of the entertainment angle would will be:
13.jamie adds his marks for his 6 exams.he has a median ogf 60.calculate the missing number.
50,54,58,x,62,68
ffice:eek:ffice" /><o>:p></o>:p>


10.
the answer is 70 degrees
do 140/720*360=70 degrees (this is just like finding the percentage)

13. the answer is 62 because if u add 62+58 and divide it by 2 the answer is 60.
 

supre

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14.josselyn earns $400 a week.she spends $280.calculate the percentage of her pay that is left.
33.jim bought a box of cd’s for $45.they had been reduced by 10%.this means they were originally marked
a.$50 b.49.50 c.$40.50 d.$4.50
14. $400-$280=$120
$120/400*100=30% of her pay is left

33. the answer is $50 because 10% of $50 is $5 and 50-5=$45
 

supre

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48.debra borrows $1500 for 3 years.interest is charged at $75 per month.how much will she pay back in total?
a.$900 b.$2,700 c.$15,900 d.$17,700
thanx in advance
48. $75*(3*12)=$2700
$2700+$1500=$4200
but this answer is not an option so there is a high chance that i might be wrong.

correct me if i am wrong, please.
;);)

and also sorry for solving these answers in separate posts rather than one, i couldnt be bothered doing all that at the same time.

:devil::lol:
 
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