Q&A - P5 Math

[zeemimi]

this is a P5 question. My DS just did this yesterday.

[zinc6539]

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P5 Maths 2011 SA2 CHIJ Qn 24

Pls help to solve, thks. Ans given is 330 deg.

[zeemimi]

zinc6539:

http://img.photobucket.com/albums/v187/veron/Capture2.jpg\">


P5 Maths 2011 SA2 CHIJ Qn 24

Pls help to solve, thks. Ans given is 330 deg.

s = 60

t + u + v = 360 - 90 = 270

total = 270 + 60 = 330

[zinc6539]

Thanks! Now then I remember that the interior angles of a 4-sided figure always add up to 360 degrees. =P

[Easy-going]

Hi

Please help me in this P5 Nanyang Primary School Maths Question
16

[Easy-going]

Hi

Please help me in this P5 Nanyang Primary School Maths Question:
Question16) Mr Chen bought some pencil cases and bags for the children at a gathering. The price of each pencil case was $2.40 while the price of each bag was $10.80. For every 4 bags bought, he was given one such pencil case for free. After receiving the free pencil cases, the number of pencil cases was 1/3 of the number of bags bought.
If Mr Chen paid a total of $1584, how much more did he pay for the bags than the pencil cases? :? :? :?:

Thanks in advance :thankyou:

[lapapillion]

dazzlego:

The shaded area in this diagram is actually the number of students.
Therefore, Blue shaded = Red shaded
Blue shaded = 24 x 1 unit + 32 x 5 = 24 units + 160
Red shaded = 26 x 1 unit + 26 x 5 = 26 units + 130
2 units = 30
1 unit = 15
total no. of class now: 15 + 5 = 20
average no. of students now = 26
total no. of students = 20 x 26 = 520

Cheers :celebrate:

Wow, brilliant! I never thought of that!

[shawnlim88]

Easy-going:

Hi

Please help me in this P5 Nanyang Primary School Maths Question:
Question16) Mr Chen bought some pencil cases and bags for the children at a gathering. The price of each pencil case was $2.40 while the price of each bag was $10.80. For every 4 bags bought, he was given one such pencil case for free. After receiving the free pencil cases, the number of pencil cases was 1/3 of the number of bags bought.
If Mr Chen paid a total of $1584, how much more did he pay for the bags than the pencil cases? :? :? :?:

Thanks in advance :thankyou:

every 4 bags 1 free pencil case
no of bags = 3 x No of pencil case
so Mr chen must buy 12bags and 1 pencil case ( +3 free )
ie: 12 bags = 3 x ( 1 -bought + 3 - free)
he must buy 12 bags and 1 pencil case ( 1 set )
cost of 1 set : = 12*10.80 + 2.40 = 132
Either:
A
>>>>>>>>>>>
he can buy 1584 / 132 sets = 12 sets
each set, he pay 12 bags = $129.6
1 pencil case: 2.4
so each set he pays ( 129.6 - 2.4) more $127.2

he bought 12 sets: so 12 * 127.2 = 1526.4
>>>>>>>>>>>>>
or B:
>>>>>>>>>>>>>>>
he can buy 1584 / 132 = 12 sets of ( 12 bags & 1 pencil case)
for 12 sets: he paid: 12*12* 10.80 for bags = 1555.2 for bags
for 12 sets: he paid : 12 * 1 * 2.4 for pencil cases: = 28.8 for pencil cases

so he paid ( 1555.2 - 28.8 ) = 1526.4 more for bags than pencil case.
>>>>>>>>>>>>>>>

Answer: 1526.4

[shawnlim88]

hi all,

how to solve this Rosyth 2011 SA2 Paper 2, Qn16 using models.

Q16: Don and Larry had 315 stickers altogether. Don gave 1/4 of his stickers to Larry. After that, Larry gave 1/2 of all that he had to Don. In the end, Don had twice as many as Larry
a) How many stickers did Don have at first? ( 140 )
b) How many stickers did Larry have at last? ( 175 )

thanks.

[Suz855]

D[ ][ ] 210

L[ ]105

315/3=105 (b)

Since L give 1/2 away, half is left,
L: 105*2=210
105

Since D give 1/4, 3/4–> 105
1/4–> 35
Thus D 105+35=140

It is a working backward problem, modeling not v useful in solving, cheers