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(a) + 1 3 5 2 3 5 7 3 4 6 8 4 5 7 9 Sample space = 9 Sum greater than 3 but less than 7 = {5, 4, 6, 5} = 4 P(sum greater than 3 but less than 7) = \(\frac{4}{9}\). (b) Given that y + m = 90^\circ < ABE = x^\circ (vertically opp. angles) < BAD = (x + m)^\circ (exterior angles) < DCB = (x + y)^\circ (exterior angles) (x + m)^\circ + (x + y)^\circ = 180^\circ (opp. angles of a cyclic quadrilateral) (2x + y + m)^\circ = 180^\circ (2x + 90) = 180 2x = 180 - 90 = 90^\circ x = 45^\circ

\(T_{n} = ar^{n - 1}\) (terms of a geometric progression) \(T_{3} = ar^{3 - 1} = ar^{2} = 360 ... (1)\) \(T_{6} = ar^{6 - 1} = ar^{5} = 1215 ... (2)\) Divide (2) by (1). \(\frac{ar^{5}}{ar^{2}} = \frac{1215}{360}\) \(r^{3} = \frac{27}{8}\) \(\therefore r = \sqrt[3]{\frac{27}{8}} = \frac{3}{2}\) (b) Putting r in (1), we have \(ar^{2} = 360\) \(a \times (\frac{3}{2})^{2} = 360 \implies \frac{9a}{4} = 360\) \(a = \frac{360 \times 4}{9} = 160\) (c) \(S_{n} = \frac{a(r^{n} - 1)}{r - 1}\) (sum of terms of a G.P) \(S_{4} = \frac{160((\frac{3}{2})^{4} - 1)}{\frac{3}{2} - 1}\) = \(\frac{160(\frac{81}{16} - 1)}{\frac{1}{2}}\) = \(\frac{160 \times \frac{65}{16}}{\frac{1}{2}}\) = \(1300\)

(a) Cost price of a radio = N6,000.00 \(\therefore\) 30% profit = \(\N6000 \times \frac{30}{100} = N1800\) \(\therefore\) Marked price = N(6000 + 1800) = N7800 Final Selling price = \(\frac{100 - 10}{100} \times N7800 = N7020\) Profit = N(7020 - 6000) = N1020. \(\therefore\) % profit = \(\frac{1020}{6000} \times 100% = 17%\) (b) \(2^{(2x + 1)} - 9(2^{x}) + 4 = 0\) \((2^{x})^{2} \times 2 - 9(2^{x}) + 4 = 0\) Let \(2^{x} = y\) \(2y^{2} - 9y + 4 = 0\) \(2y^{2} - 8y - y + 4 = 0\) \(2y(y - 4) - 1(y - 4) = 0\) \((2y - 1)(y - 4) = 0\) \(2y = 1 \implies y = \frac{1}{2}; y = 4\) \(y = \frac{1}{2} \implies 2^{x} = \frac{1}{2} = 2^{-1} \) \(x = -1\) \(y = 4 \implies 2^{x} = 4 = 2^{2}\) \(x = 2\) \(\therefore x = -1, 2\)

x -3 -2 -1 -0.5 0 1 2 y -28 -5 6 7 5 -8 -33 (b)(i) (c)(i) \(2 - 7x - 6x^{2} = 0\) \(2 + 3 - 7x - 6x^{2} = 3\) \(5 - 7x - 6x^{2} = 3\) \(\therefore \text{the roots at y = 3 are } x = -1.4; 0.2\) (ii) Maximum value of \(y = 5 - 7x - 6x^{2}\) is y = 7.

(a) (b)(i) PS = 6.0cm (ii) Perpendicular disstance between RS and PQ i.e. RK = 5.9cm (iii) QRSP is a trapezium.

XWZ = 90^\circ - (45^\circ + 23^\circ) = 22^\circ WYX = 180^\circ - (45^\circ + 95^\circ) = 40^\circ < XZW = 180^\circ - (89^\circ + 22^\circ) = 69^\circ (a)(i) \(\frac{XY}{\sin 95} = \frac{180}{\sin 40^\circ}\) \(XY = \frac{180 \sin 95}{\sin 40} = 278.96m\) \(\approxeq 279m\) (ii) \(\frac{ZW}{\sin 89^\circ} = \frac{180}{\sin 69^\circ}\) \(ZW = \frac{180 \sin 89^\circ}{\sin 69^\circ} = 192.76m\) \(\approxeq 193m\) (b) < ZNX =

Source: Myschool Past Questions Archive (Record #54452)