2008 non-calculator questions..help (1 Viewer)

[Riot09]

2008 mathematics school certificate..need help very tricky questions mostly geometry

please include working out and a explanation all the diagram question can be found on the link below.

http://www.boardofstudies.nsw.edu.au/schoolcertificate/sc2008/2008-SCT-mathematics.pdf

q.22the circumference of this circle is 31.4.the diameter is 10cm.

calculate the perimeter of the shaded semi-circle.(without a calculator)

q.32 is a diagram question

q.41,43,46,56,59,62,64,65,66,67,70,71,72,73,75,80,81 and 83 would be greatly appreciated

 

[Absolutezero]

Q22.

C= 31.4

Thus, 1/2 C = 15.7

1/2 C + D = 15.7 + 10

=25.7

32.

Sin = OPP/HYP

Sinx = 4/5

4/5 = Can't achieve with Tan in diagram

4/5 = Sin is already accounted for

Thus, 4/5 must be cos

Cos y = 4/5

Thus, answer is c

 

[Absolutezero]

Q41.

3 texts = 25 x 3

=75

Call = Connection + 38.5 per 30 sec

=27 + 38.5 * (rounding up of 275/30)

=27 + 385

All up,
$4.87

Q42.

10 parts

Treadmill for 3/10 of day

24/ 3 for one part = 6

10 parts = 60

Therefore, at gym for 60 minutes

 

[Absolutezero]

Going through this in parts, to give me time to work them out. And so my internet doesn't cut out before they're posted.

46.
a) 125/280 = 0.44

b) 200/455 = 0.439

c)500/1095 = 0.456

d)750/1650 =0454

Thus, b

56.

4 sided shape = 360

360 - 70 = 290 degree inside angle

290 + 10 + 20 = 320

360 - 320 = y

y = 40

Thus, d

 

[Absolutezero]

59.

Square = s, Circle = c, Triangle = T

4s = 3T ---------eq 1

2T = 5c ---------eq2

eq 1 x2 , eq 2 x 3

4s = 6T ------eq3

6T = 15c ----eq4

4s = 6T = 15c

Therefore, Heaviest to lightest

Square, Triangle, Circle: The answer is c


62.

Turn shape to get angles facing same direction, and you will see that 60 corresponds with 3

Thus, answer is 20 (c)

 

[Absolutezero]

64.

19.35 * 1.5 = 29.025

@6hrs = 174.15

696.60 -174.15 = 522.45

522.45 / 19.35 = 27

(B) 27


65.

Area of small trap = 1/2h (a+b)

a = 2b

=1/2 h(3)

A of big Trap 1/2h (a + b)

=1/2h (3 + 2)

= 2.5 h

Little/ Big

1.5/2.5

3/5

Thus, c


66.

n is whole

Thus, 2n is always even

Therefore, 2n + 1 is always odd. Answer is b

 

[Absolutezero]

67.
d= 2r

r=40

40cm = 0.4m

Cycl = Pi r^2 h

1/2 Cycl

Therefore, Pi x 0.4^2 x 1.2

(a)

70.

Unnamed angle, lets call it a

a = 180 - 5x (cointerior)

2x + a = 3x (alt)

a = x

Thus,
x=180 - 5x

6x =180

x = 30 (b)

 

[Absolutezero]

71.

(2x + 1) x 10 - (3x5)

20x +10 - 15

= 20x - 5

72.
in 15min

60km travels 15m

80km travel 20 km

Therefor, 25km apart d

You may want a second opinion on this, I think its right though.

73.
Just break it down

A1 is 1:2

A2 is 1:4

A3 is 1:8

A4 is 1:16

 

[Absolutezero]

75.
X = 1/4, y = 1/2

Half of x is 1/8

1/8 + 1/2 = 5/8

Therefore, empty is 3/8


80.
Total votes 10 700
20% of 1000 left = 200

max votes for Isaac is 5000 + (maximum of) 50% of 1000= 5500

Thus, min votes for Sam is 5200


Max for Sam is 4700 + 80% (which is 50% guarantee + (100 - 20)) of 1000

= 5500

Min for Issac is thus 5200

All are correct