If \(M=-8\), what is the value of \(\dfrac{4M^2+3M}{8}\)
- \(-1027\)
- \(-35\)
- \(29\)
- \(125\)
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If \(M=-8\), what is the value of \(\dfrac{4M^2+3M}{8}\)
\(C\)
| \(\dfrac{4M^2+3M}{8}\) | \(=\dfrac{4\times (-8)^2+3\times (-8)}{8}\) |
| \(=\dfrac{4\times 64-24}{8}\) | |
| \(=\dfrac{232}{8}\) | |
| \(=29\) |
\(\Rightarrow C\)
What is the value of \(\sqrt{\dfrac{2x + y}{5x}}\) if \(x=5.1\) and \(y=3.7\), correct to 2 decimal places?
\(B\)
| \(\sqrt{\dfrac{2x+y}{5x}}\) | \(=\sqrt{\dfrac{2\times 5.1+3.7}{5\times 5.1}}\) |
| \(=\sqrt{\dfrac{13.9}{25.5}}\) | |
| \(= 0.7383\dots\) |
\(\Rightarrow B\)
This shape is made up of two right-angled triangle and a regular hexagon.
The area of a regular hexagon can be estimated using the formula \(A=2.598S^2\) where \(S\) is the hexagon's side-length.
Calculate the total area of the shape using this formula. (3 marks)
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\(619.6\ \text{cm}^2\)
\(\text{Area}=2.598S^2\)
\(\text{Using Pythagoras}\)
\(S^2= 10^2+10^2=200\)
\(S=\sqrt{200}\)
\(A=2.598\times (\sqrt {200})^2=519.6\ \text{cm}^2\)
\(\text{Area of Δ}\ =\dfrac{1}{2}bh=\dfrac{1}{2}\times 10\times 10=50 \ \text{cm}^2\)
\(\therefore\ \text{Total Area}\ =519.6+50+50=619.6\ \text{cm}^2\)
What is the value of \(\dfrac{x-y}{6}\), if \(x=184\) and \(y=46\)?
\(B\)
| \(\dfrac{x-y}{6}\) | \(=\dfrac{184-46}{6}\) |
| \(=23\) |
\(\Rightarrow B\)
If \(V=\dfrac{4}{3}\pi r^3\), what is the value of \(V\) when \(r = 5\), correct to two decimal places?
\(D\)
\(V =\dfrac{4}{3}\pi r^3\)
\(\text{When}\ r = 2,\)
| \(V\) | \(=\dfrac{4}{3}\pi\times 5^3\) |
| \(=523.598\dots\) |
\(\Rightarrow D\)
If \(K=Ft^3\), \(F=9\) and \(t=0.829\), what is the value of \(K\) correct to three significant figures?
\(D\)
| \(K\) | \(=Ft^3\) |
| \(=9\times 0.829^3\) | |
| \(=5.1275\dots\) | |
| \(=5.13\ \text{(3 sig figures)}\) |
\(\Rightarrow D\)
What is the value of \(4m^2-n\), if \(m=−3\) and \(n=1\). (2 marks)
\(35\)
| \(4m^2-n\) | \(=4(−3)^2-1\) |
| \(=4\times 9-1\) | |
| \(=35\) |
If \(A=P(1 + r)^n\), find \(A\) given \(P=$500\), \(r=0.09\) and \(n=5\) (give your answer to the nearest cent). (2 marks)
\($769.31\ \text{(nearest cent)}\)
| \(A\) | \(=P(1 + r)^n\) |
| \(=500(1 + 0.09)^5\) | |
| \(=500(1.09)^5\) | |
| \(=769.311\dots\) | |
| \(=$769.31\ \text{(nearest cent)}\) |
It is given that \(I=\dfrac{3}{2}MR^2\).
What is the value of \(I\) when \(M =19.12\) and \(R = 1.02\), correct to two decimal places?
\(B\)
| \(I\) | \(=\dfrac{3}{2}\times 19.12\times 1.02^2\) |
| \(=29.84\) |
\(\Rightarrow B\)
If \(S = V_0(1 - r)^n\), find \(S\) given \(V_0 = $57\ 000\), \(r = 0.12\) and \(n=5\). (give your answer to the nearest cent). (2 marks)
\($30\ 080.72\ \text{(to nearest cent)}\)
| \(S\) | \(=V_0(1 – r)^n\) |
| \(=57\ 000 (1-0.12)^5\) | |
| \(=57\ 000 (0.88)^5\) | |
| \(=$30\ 080.719\dots\) | |
| \(=$30\ 080.72\ \text{(to nearest cent)}\) |
What is the value of \(\dfrac{x+y}{xy}\) if \(x=-4.3\) and \(y=-2.4\), correct to 1 decimal place? (2 marks)
\(-0.6\ \text{(1 d.p.)}\)
| \(\dfrac{x+y}{xy}\) | \(=\dfrac{-4.3+(-2.4)}{-4.3\times -2.4}\) |
| \(=\dfrac{-6.7}{10.32}\) | |
| \(=-0.649\dots\) | |
| \(\approx-0.6\ \text{(1 d.p.)}\) |