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 a right-angled triangle and a regular hexagon.
The area of a regular hexagon can be estimated using the formula \(A=2.598H^2\) where \(H\) is the side-length.
Calculate the total area of the shape using this formula. (3 marks)
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\(51.264\ \text{cm}^2\)
\(\text{Area}=2.598H^2\)
\(\text{Using Pythagoras}\)
\(H^2\) | \(= 3^2+3^2\) |
\(=18\) | |
\(H\) | \(=\sqrt{18}\) |
\(\therefore\ \text{Area of hexagon}\) | \(=2.598\times {\sqrt {18}}\ ^2\) |
\(=46.764\ \text{cm}^2\) |
\(\text{Area of triangle}\) | \(=\dfrac{1}{2}bh\) |
\(=\dfrac{1}{2}\times 3\times 3\) | |
\(=4.5\ \text{cm}^2\) |
\(\therefore\ \text{Total Area}\) | \(=46.764+4.5\) |
\(=51.264\ \text{cm}^2\) |
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)
\(-0.6\ \text{(1 d.p.)}\)
\(\dfrac{x+y}{xy}\) | \(=\dfrac{-4.3+(-2.4)}{-4.3\times -2.4}\) |
\(=\dfrac{-6.7}{10.32}\) | |
\(=-0.649\dots\) | |
\(\approx-0.6\ \text{(1 d.p.)}\) |