(a) The diagram, = IWYI = IXZI and < WXY = 80(^o). What is the size of < XWZ?
(b) A man was charged 2 kobo per month for every N1.00 he borrowed from a bank. At what rate per annum was the interest charged?
Explanation
(a) First joining XZ and WY, we have < XWY = < XZY = (frac{1}{2})(180° — 80°) = 50°. This implies that < ZXY = 50°(base angles of an isosceles triangle). So that < XWZ = 180° – 80° = 100°.
(b) The rate in every N1.00 = (frac{2}{100}) so that the rate of interest charged per annum will be (frac{2 times 12}{100}) x 100 which gives 24%.