# 2017 A-level H1 Mathematics (8865) Paper 1 Suggested Solutions All solutions here are SUGGESTED. Mr. Teng will hold no liability for any errors. Comments are entirely personal opinions.

Numerical Answers (click the questions for workings/explanation)

Question 1:
Question 2:
Question 3:
Question 4:
Question 5:
Question 6: Question 7: Question 8: Question 9: ; latex 0.0336; \bar{y}=0.64, s^2 = 0.0400 latex \frac{48+x}{80+x}, \frac{32+x}{80+x}; x= 16; \frac{25}{32}; \frac{7}{16}; \frac{341}{8930} latex 0.773; 0.0514; 0.866; 0.362 latex X latex X \sim \text{N} (\mu, \sigma^2) latex \text{P}( X \textless 1.6) = 0.2latex \text{P}( Z \textless \frac{1.6 – \mu}{\sigma}) = 0.2latex \frac{1.6 – \mu}{\sigma} = -0.8416212335 latex 1.6 = -0.8416212335 \sigma + \mu latex \text{P}( X \textgreater 1.75 ) = 0.3latex \text{P}( X \textless 1.75 ) = 0.7latex \text{P}( Z \textless \frac{1.75 – \mu}{\sigma} ) = 0.7latex \frac{1.75 – \mu}{\sigma} = 0.5244005101latex 1.75 = 0.5244005101 \sigma + \mu latex \mu = 1.69241, \sigma = 0.1098079154 latex = 1.69 latex = 0.0121 latex X latex X \sim \text{B}(8, 0.7)latex \text{P}(X =5) = 0.254 latex Y latex Y \sim \text{B}(8, 0.3)latex \text{P}(Y \ge 4)latex = 1 – \text{P}(Y le 3)latex = 0.19410435 \approx 0.194 latex W latex W \sim \text{B} (6, 0.19410435)latex \text{P} ( W \le 2)latex = 0.9082304639 \approx 0.908 latex {{6}\choose{3}} \times 3! \times {{8}\choose{3}} \times 3! = 40320 latex \bigg[ {{5}\choose{1}} \times \frac{3!}{2!} + {{5}\choose{2}} \times 3! \bigg] \times {{7}\choose{1}} \times \frac{3!}{2!} = 1575 latex = \frac{1575}{6^3 \times 8^3} = 0.0142 latex \text{P}(\text{has~}2\text{~as~its~first~character}) = \frac{1}{6}latex \text{P}(\text{has~H~as~its~sixth~character}) = \frac{1}{8}latex \text{P}(\text{has~}2\text{~as~its~first~character~and~has~H~as~its~sixth~character}) = \frac{1}{6 \times 8} = \frac{1}{48} latex = \frac{1}{6} + \frac{1}{8} – 2(\frac{1}{48}) = \frac{1}{4} latex \text{r}=0.978 latex a=0.182, b=2.56 latex y = 0.1821185456 x + 2.564419724 latex x = 2, y = 0.1821185456 (2) + 2.564419724latex \Rightarrow y = 2.9287 293.

(v)
Firstly, the linear model is not appropriate here. Since it suggests as the number of years increases, the weekly earnings will increase proportionately, which is not realistic.

Secondly, is out of data range and this is extrapolation, which is a bad practice since our trend might not continue out of data range.
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MF26

• Leah

• KS Teng

yes, sorry was having a H2 math class for J2 just now.

• Leah

it’s ok!! Thank u for doing this 🙂

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