# 2009 June(67C) Math Question 1

Choice A

$$\Rightarrow 20\times v+10\times p$$

# 2009 June(67C) Math Question 2

Choice F

$$(9+5-(-6))(5+(-6))$$ $$=(20)(-1)$$ $$=-20$$

# 2009 June(67C) Math Question 3

Choice E

$$1st\ machine:60\times8=480$$ $$2nd\ machine:80\times6=480$$ $$\Rightarrow 480+480=960$$

# 2009 June(67C) Math Question 4

Choice J

$$210+225+254+231+280=1200$$ $$1200\div5=240$$ $$(1200+240)\div6=240$$

# 2009 June(67C) Math Question 5

Choice C

$$40\times7.5+2\times7.5\times1.5$$ $$=300+22.5$$ $$=322.5$$

# 2009 June(67C) Math Question 6

Choice K

$$\Rightarrow x^{2}=39+10x$$

# 2009 June(67C) Math Question 7

Choice E

$$9(x-9)=-11$$ $$\Rightarrow 9x-81=-11$$ $$\Rightarrow 9x=70$$ $$\Rightarrow x=\frac{70}{9}$$

# 2009 June(67C) Math Question 8

- Cost

Choice H

$$60\div4=15$$ $$15\times x=60+37.5$$ $$15x=97.5$$ $$x=6.5$$

# 2009 June(67C) Math Question 9

- FOIL

Choice A

$$=(3x)(3x+4y^{2})-(4y^{2})(3x+4y^{2})$$ $$=(9x^{2})+(12xy^{2})-(12xy^{2})-(16y^{4})$$ $$=9x^{2}-(16y^{4})$$

# 2009 June(67C) Math Question 10

Choice J

$$WL=32$$ $$2(W+L)=24$$ $$W+L=12$$ $$W=4,L=8$$

# 2009 June(67C) Math Question 11

Choice D

$$180° − 47° = 133°$$

# 2009 June(67C) Math Question 12

Choice K

$$3\times3\times4\times2=72$$

# 2009 June(67C) Math Question 13

Choice B

Consecutive integers can be represented as (n, n + 1).

$$n+ 3 n + 1 = 79$$ $$4n + 3 = 79$$ $$n = 19$$

# 2009 June(67C) Math Question 14

Choice F

$$f(-3)=-8(-3)^{2}$$ $$=-8(9)$$ $$=-72$$

# 2009 June(67C) Math Question 15

Choice C

$$3^{x}=54$$ $$3^{3}=27$$ $$3^{4}=81$$ $$\Rightarrow 3^{3}\lt 3^{x}\lt 3^{4}$$ $$\Rightarrow 3\lt {x}\lt {4}$$

# 2009 June(67C) Math Question 16

Choice J

$$70=7\times10$$ $$60=6\times10$$ $$50=5\times10$$ $$7\times6\times5\times10=2100$$

# 2009 June(67C) Math Question 17

Choice B

$$Volume\ of\ a\ box\ =81,000$$ $$81,000=45\times30\times h$$ $$h=60$$

# 2009 June(67C) Math Question 18

Choice J

$$\Rightarrow A,C,D,B$$

# 2009 June(67C) Math Question 19

Choice D

$$t=5$$ $$y=16(2)^{5}=512$$

# 2009 June(67C) Math Question 20

Choice J

$$Smaller\ Rectangle=l\cdot w=A$$ $$Larger\ Rectangle=3l \cdot w =kA$$ $$k=3$$

# 2009 June(67C) Math Question 21

Choice E

$$=(a-4a)+(2b-6b)+(3c+5c)$$ $$=-3a-4b+8c$$

# 2009 June(67C) Math Question 22

Choice G

$$\sin\theta=\frac{Opp}{Hyp}$$ $$\sin\theta=\frac{a}{c}$$

# 2009 June(67C) Math Question 23

Choice B

Let five players be A, …

# 2009 June(67C) Math Question 24

Choice H

$$y=0.12x+3000$$ $$\Rightarrow m=0.12$$ $$0.12+0.1=0.22$$

# 2009 June(67C) Math Question 25

Choice A

$$=-8(7)(x^{3+6})+(-8)(-3)(x^{3+5})$$ $$=-56x^{9}+24x^{8}$$

# 2009 June(67C) Math Question 26

Choice G

$$=-3\mid2\mid$$ $$=-3(2)$$ $$=-6$$

# 2009 June(67C) Math Question 27

Choice B

$$3-4-5\ triangle \Rightarrow \overline{BC}=5$$ $$\overline{AC}:\overline{BC}=20:5=4:1$$ …

# 2009 June(67C) Math Question 28

Choice H

“Constant rate.” - This is …

Choice E

# 2009 June(67C) Math Question 41

Choice B

$$ay+bx=x$$ $$ay$$ $$\Rightarrow y=-\frac{b}{a}+\frac{c}{a},\ m=-\frac{b}{a}$$ …

# 2009 June(67C) Math Question 42

Choice F

From the angle of 52, …

# 2009 June(67C) Math Question 43

Choice D

Odd- in age: not in …

# 2009 June(67C) Math Question 44

Choice H

“Lines of symmetry” are lines …

Choice A

# 2009 June(67C) Math Question 48

Choice H

Arc angle is twice the …

# 2009 June(67C) Math Question 49

Choice B

Infinite solutions means “same line.” …

Choice F

- Cost

Choice C