# 2015 June(73C) Math Question 1

Choice C

$$a(4-a)-5(a+7)=4a-a^2-5a-35=-a^2-a-35$$

# 2015 June(73C) Math Question 2

Choice G

$$\frac{1}{4}=0.25 \\$$ $$\Rightarrow 0.03 \leq 0.2 \leq 0.25 \\$$ $$\Rightarrow 0.03 \leq 0.2 \leq \frac{1}{4}$$

# 2015 June(73C) Math Question 3

Choice C

$$x^2=29-4=25 \\$$ $$\Rightarrow x^2-4=25-4=21$$

# 2015 June(73C) Math Question 4

Choice H

Since T and U bisect QR and QS, respectively, TU//RS. Thus, $$\angle TUQ=\angle S=60° \\$$ $$\Rightarrow \angle TUS=180°-\angle TUQ=180°-60°=120°$$

# 2015 June(73C) Math Question 5

Choice C

The line is going downwards. Therefore the slope is negative.

# 2015 June(73C) Math Question 6

Choice K

$$\sqrt{81}=9 \\$$ $$\sqrt{99}\approx\sqrt{100}=10$$ $$\\ 9 \leq 9.2371 \leq 10 \\$$ $$\Rightarrow 81\leq the \ number \leq 99$$

# 2015 June(73C) Math Question 7

Choice E

$$p=\frac{10-2}{10}=\frac{4}{5}$$

# 2015 June(73C) Math Question 8

Choice K

$$\frac{x_{A}+(-3)}{2}=1 \\$$ $$\Rightarrow x_{A}=5 \\$$ $$\frac{y_{A}+4}{2}=2 \\$$ $$\Rightarrow y_{A}=0$$

# 2015 June(73C) Math Question 9

Choice B

$$2x+8=116 \\$$ $$\Rightarrow x=54$$

# 2015 June(73C) Math Question 10

Choice H

$$500+200x=2,200 \\$$ $$\Rightarrow x=8.50$$

# 2015 June(73C) Math Question 11

- FOIL

Choice D

$$(3x+6)(2x-1)=6x^2-3x+12x-6=6x^2+9x-6$$

# 2015 June(73C) Math Question 12

Choice J

A box of 25 candies at Tamika's Treat costs $4.25. Thus the money left is$10.00 - $4.25 =$5.75, which is 23 quarters: $$\frac{5.75}{0.25}=23$$

# 2015 June(73C) Math Question 13

Choice B

$$\frac{3.75}{20}=0.1875\approx 0.19$$

# 2015 June(73C) Math Question 14

Choice F

Only the equation in F fulfils all the given prices and the number of candies given in the table.

# 2015 June(73C) Math Question 15

Choice E

The opposite of 'at least 1' is 'no one'.

Choice J

# 2015 June(73C) Math Question 17

Choice E

$$\frac{9\times9\times12}{3\times3\times3}=36$$

# 2015 June(73C) Math Question 18

Choice J

$$f(-4)=-4(-4)^{3}-4(-4)^{2} =-4(-64)-4(16) =256-64 =192$$

# 2015 June(73C) Math Question 19

Choice A

$$x+2y=4 \\$$ $$-2x+y=7 \\$$ $$\Rightarrow x=-2, \ y=3$$

# 2015 June(73C) Math Question 20

Choice G

$$x=\sqrt{8^2+9^2}\approx12 \\$$ $$Perimeter = 8+10+12+19=49\approx50$$

# 2015 June(73C) Math Question 21

Choice C

$$5\times7-4\times6=11$$

Choice H

Choice A

# 2015 June(73C) Math Question 31

Choice B

$$3k+5k+3k+5k=96 \ cm \\$$ …

Choice G

Choice H

12 - 3.6 = 8.4

Choice A

4 - 1 = 3

# 2015 June(73C) Math Question 38

Choice J

$$P=\frac{3^ne^{-3}}{n!}=\frac{3^2\times0.05}{2!}\approx0.23$$

# 2015 June(73C) Math Question 39

Choice B

The amplitude of f(x)=cos(x) is …

# 2015 June(73C) Math Question 40

Choice H

$$\frac{4}{3}\pi x^3=12 \\ \Rightarrow x=\sqrt[3]{\frac{9}{\pi}}$$

# 2015 June(73C) Math Question 41

Choice D

The median will be the …

# 2015 June(73C) Math Question 42

Choice H

$$\tan40°=\frac{height}{50}\\$$ $$\Rightarrow height=50\times\tan40°=42$$

# 2015 June(73C) Math Question 43

Choice B

Sea Horse: $$\frac{255-50-50}{0.25}=620$$ Ocean Blue: …

# 2015 June(73C) Math Question 44

Choice G

0.05 fits the data best.

Choice A

# 2015 June(73C) Math Question 47

Choice E

$$\frac{12x^6}{3x^2}-\frac{9x^2}{3x^2}=4x^4-3$$

Choice K

XZ is undefined.

# 2015 June(73C) Math Question 49

Choice D

$$2x=5\times7 \\$$ $$\Rightarrow x=17.5$$

Choice F

# 2015 June(73C) Math Question 53

Choice E

Since the given equation is …

# 2015 June(73C) Math Question 54

Choice J

The slopes of two lines …

# 2015 June(73C) Math Question 55

Choice A

The shaded area lies below …

# 2015 June(73C) Math Question 56

Choice K

$$(\sqrt{3})^{j}=27^{k}$$ $$(3^{\frac{1}{2}})^{j}=(3^{3})^{k}$$ $$\frac{j}{2}=3k$$ $$j=2\times3k$$ $$\frac{j}{k}=6$$ …

# 2015 June(73C) Math Question 57

Choice A

For an arithmetic sequence, the …

# 2015 June(73C) Math Question 58

Choice F

$$sin\theta=\frac{1}{4}$$ $$\Rightarrow sin(\frac{1}{4})^{-1}=\theta$$ arc\ length=2\pi …

# 2015 June(73C) Math Question 59

Choice D

The asymptote of a function …

# 2015 June(73C) Math Question 60

Choice F

Conic sections are the result …