# 2019 June(72F) Math Question 1 Choice E

$$\frac{4}{y}=0.4$$ $$\Rightarrow \frac{4}{y}\times y=0.4\times y$$ $$\Rightarrow 4=0.4y$$ $$\Rightarrow y=10$$

# 2019 June(72F) Math Question 2 Choice J

$$60\times1.24=74.4$$

# 2019 June(72F) Math Question 3 Choice C

$$10\times40+10\times(1\frac{1}{2})\times7$$ $$=400+105$$ $$=505$$

# 2019 June(72F) Math Question 4 Choice J

$$3x^{9}\cdot 5x^{9}$$ $$=3\times5\times x^{9+9}$$ $$=15x^{18}$$

# 2019 June(72F) Math Question 5 Choice B

$$T=\pi r^{2}+\pi rs$$ $$T=\pi 3^{2}+\pi \times3\times5$$ $$=9\pi+15\pi$$ $$=24\pi$$

# 2019 June(72F) Math Question 6 Choice K

$$180°-45°-65°=70°$$

# 2019 June(72F) Math Question 7 Choice B

$$35=5\cdot7$$ $$28=2\cdot2\cdot7$$ $$8=2\cdot2\cdot2$$ $$2\cdot2\cdot2\cdot5\cdot7=280$$

# 2019 June(72F) Math Question 8 $$x=-2,5$$ $$f(x)=(x-5)(x+2)^{2}$$ $$f(-2)=0$$ $$f(5)=0$$

# 2019 June(72F) Math Question 9 Choice F

$$60\div(3+5+7)=60\div15=4$$ $$4\times7=28$$

# 2019 June(72F) Math Question 10 Choice F

$$f(9)=6$$ $$f(12)=8$$ $$F.\ f(x)=\frac{2}{3}n$$ $$f(9)=\frac{2}{3}\times9=6$$ $$f(12)=\frac{2}{3}\times12=8$$

# 2019 June(72F) Math Question 11 Choice C

$$(\frac{2+8}{2}，\frac{5+11}{2})=(5，8)$$

# 2019 June(72F) Math Question 12 Choice F

$$1\times1\times\frac{1}{9}=\frac{1}{9}$$

# 2019 June(72F) Math Question 13 Choice C

$$=3x^{2}+x^{2}-4x-6x-5-7$$ $$=4x^{2}-10x-12$$

# 2019 June(72F) Math Question 14 Choice H

22 is even.

22 is not prime.

# 2019 June(72F) Math Question 15 Choice C

$$=\mid-42+32\mid=\mid-10\mid=10$$

# 2019 June(72F) Math Question 16 Choice G

$$11x+6y=3$$ $$y=\frac{-11}{6}x+3$$

# 2019 June(72F) Math Question 17 Choice A

$$g(2,4,3)$$ $$=4\times2\times4-3\times2\times (-3)^{2}$$ $$=32-54=-22$$

# 2019 June(72F) Math Question 18 Choice H

$$x°:360°=5000:45000$$ $$\Rightarrow x=40°$$

# 2019 June(72F) Math Question 19 Choice A

$$4000\div5=800$$

# 2019 June(72F) Math Question 20 $$3000:9000=1:3=\frac{1}{3}$$

# 2019 June(72F) Math Question 21 Choice E

# 2019 June(72F) Math Question 23 Choice D

# 2019 June(72F) Math Question 26 Choice F

# 2019 June(72F) Math Question 28 Choice F

# 2019 June(72F) Math Question 30 Choice J

# 2019 June(72F) Math Question 32 Choice K

$$(3.5+0.25n)(2500-100n)$$

# 2019 June(72F) Math Question 33 Choice B

# 2019 June(72F) Math Question 35 Choice C

# 2019 June(72F) Math Question 40 Choice J

# 2019 June(72F) Math Question 42 Choice K

# 2019 June(72F) Math Question 44 Choice K

x quarters,

x+5 dimes …

# 2019 June(72F) Math Question 45 # 2019 June(72F) Math Question 47 Choice E

# 2019 June(72F) Math Question 50 Choice G

# 2019 June(72F) Math Question 52 Choice J

All real numbers except 7.

# 2019 June(72F) Math Question 53 Choice D By the Law of Sines …

# 2019 June(72F) Math Question 54 Choice G

# 2019 June(72F) Math Question 58 Choice G # 2019 June(72F) Math Question 60 Choice G B is between D and …