Choice B

# 2010 December(69A) Math Question 2

Choice H

The area of a rectangle:

$$3\times4=12$$ $$12\times3=36$$

# 2010 December(69A) Math Question 3

Choice C

$$(-5+8,8-5)=(3,3)$$

# 2010 December(69A) Math Question 4

Choice H

$$18000\times2=36000$$ $$83000-36000=47000$$ $$\frac{47000}{7000}=6.7$$

You will need 7 trucks.

# 2010 December(69A) Math Question 5

Choice D

$$15=3\times5$$ $$25=5\times5$$ $$30=2\times3\times5$$ $$\Rightarrow 2\times3\times5\times5=150$$

# 2010 December(69A) Math Question 6

Choice F

$$180°-96°=84°$$ $$84°\div2=42°$$

# 2010 December(69A) Math Question 7

Choice C

$$-2(x-7)=20$$ $$\Rightarrow x-7=\frac{20}{-2}=-10$$ $$\Rightarrow x=-3$$

# 2010 December(69A) Math Question 8

Choice F

$$=x^{3+3+3+3}$$ $$=x^{12}$$

# 2010 December(69A) Math Question 9

Choice B

$$=1\times0.1\times0.1=0.01$$

# 2010 December(69A) Math Question 10

Choice J

$$\frac{1.34+1.41+1.41+1.25+1.36}{5}=\frac{6.77}{5}=1.354$$

# 2010 December(69A) Math Question 11

- Cost

Choice B

$$0.03\times1.36=0.04$$ $$1.36+0.04=1.4$$

# 2010 December(69A) Math Question 12

Choice K

$$11.38 + 1.85 = 13.23 gallons$$ $$13.23\times1.36=17.99$$ $$17.99+4=21.99$$

# 2010 December(69A) Math Question 13

Choice E

$$\mid 2+(-3)\mid+(2+(-3))^{2}$$ $$=\mid-1\mid+(-1)^{2}$$ $$=1+1$$ $$=2$$

# 2010 December(69A) Math Question 14

Choice F

$$3.9\times 10^{-1}=0.39$$ $$3.9\times 10^{-2}=0.039$$ $$3.9\times 10^{-3}=0.0039$$

There will always be one less zero in front of the three and the nine.

# 2010 December(69A) Math Question 15

Choice C

$$525=7\times15\times H$$ $$\Rightarrow H=5$$

# 2010 December(69A) Math Question 16

Choice K

$$g(2)=(-3)^{2}+3=9+3=12$$

# 2010 December(69A) Math Question 17

- FOIL

Choice D

$$=5c(2d-5c)-3d(2d-5c)$$ $$=10cd-36c^{2}-6d^{2}+15cd$$ $$=25cd-36c^{2}-6d^{2}$$

# 2010 December(69A) Math Question 18

Choice G

$$\angle ADB=180°-30°-20°=130°$$ $$\angle EDA=180°-130°=50°$$ $$\angle EAD=180°-83°-50°=47°$$

# 2010 December(69A) Math Question 19

Choice D

$$x + y = 21$$ $$x – y = 15$$ $$\Rightarrow 2x=21+15=36$$ $$x=18$$ $$y=3$$ $$xy=18\times3=54$$

# 2010 December(69A) Math Question 20

Choice K

For Green Tree, the equation is 50 + 0.25m = 100, so m = 200.

For Big Rock, the equation is 60 + 0.2m= 100, so m = 200.

Therefore, she can drive the same amount of miles with either company.

# 2010 December(69A) Math Question 21

- FOIL

Choice E

$$\frac{(x-5)^{2}}{x^{2}-25}$$ $$=\frac{(x-5)(x-5)}{(x-5)(x+5)}$$ $$=\frac{(x-5)}{(x+5)}$$

# 2010 December(69A) Math Question 22

Choice F

$$\frac{3}{8}=\frac{x}{80}$$ $$x=30$$

# 2010 December(69A) Math Question 23

Choice B

Just get the decimal equivalents …

# 2010 December(69A) Math Question 24

Choice H

$$t=0,y=12,$$

The y-intercept is …

# 2010 December(69A) Math Question 25

Choice C

T is the speed of …

Choice F

# 2010 December(69A) Math Question 37

Choice D

$$2\frac{1}{6},3\frac{1}{3},4\frac{1}{2}$$

The common difference is …

# 2010 December(69A) Math Question 38

Choice G

$$B=x+2$$ $$y=A-4 \Rightarrow A=y+4$$ $$B+A=(x+2)+(y+4)=x+y+6$$

# 2010 December(69A) Math Question 39

Choice C

$$10,10,x,x$$ $$20+2x=64$$ $$x=22$$ $$\Rightarrow 10,22,22$$

Choice H

# 2010 December(69A) Math Question 41

Choice B

The midpoint of AD to …

# 2010 December(69A) Math Question 42

Choice G

The area of a rhombus: …

# 2010 December(69A) Math Question 43

Choice D

$$5\times4\times3\times2\times1=120$$

# 2010 December(69A) Math Question 44

Choice G

$$3^{2}+h^{2}=6^{2}$$ $$h=3\sqrt{3}\approx 3\times1.73=5.19$$

# 2010 December(69A) Math Question 45

Choice A

$$x^{2}\lt x$$

Only for x …

# 2010 December(69A) Math Question 46

Choice G

$$48+66=114$$

# 2010 December(69A) Math Question 47

Choice A

If the radius of the …

Choice F

# 2010 December(69A) Math Question 54

Choice F

$$\csc =\frac{hypotenuse}{opposite}=\frac{1}{\sin}$$ $$=\frac{1}{0.4}=\frac{5}{2}$$

# 2010 December(69A) Math Question 55

Choice E

If B has a slower …

# 2010 December(69A) Math Question 56

Choice K

Each of the first five …

# 2010 December(69A) Math Question 57

Choice E

If x is positive or …

# 2010 December(69A) Math Question 58

Choice J

It's in the first quadrant, …

# 2010 December(69A) Math Question 59

Choice A

Picture a vector of the …

# 2010 December(69A) Math Question 60

Choice K

$$=\frac{\sqrt{r}}{\sqrt{s}}+\frac{\sqrt{s}}{\sqrt{r}}$$ $$=\frac{\sqrt{r}\times\sqrt{r}}{\sqrt{s}\times\sqrt{r}}+\frac{\sqrt{s}\times\sqrt{s}}{\sqrt{r}\times\sqrt{s}}$$ $$=\frac{r+s}{\sqrt{rs}}$$