Theory question 109
Inequalities(a) Find the smallest integer that satisfies the inequality x + 8 < 4x − 15.
(b) A sales girl is paid a monthly salary of N2,500.00 in addition to a commission of 5 kobo in the naira on all sales made by her during the month. If her sales for a month amounts to N200,000.00, calculate her income for that month.
(c) The diagram shows a window consisting of a rectangular and a semi-circular parts. The radius of the semi-circular part is 35 cm and the height of the rectangular part is 50cm. Find the area of the window. (Take π = 22/7)
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(a) 23 < 3x, so x > 7⅔; the smallest integer is 8.
(b) Commission = 5% of 200,000 = N10,000. Income = 2,500 + 10,000 = N12,500.00.
(c) The rectangle is 70 cm wide (the diameter) and 50 cm high: 3500 cm2.
Semicircle = ½ × 22/7 × 352 = 1925 cm2. Window = 3500 + 1925 = 5425 cm2.
5 kobo in the naira is 5%.