(a) It takes 8 students two- thirds of an hour to fill 12 tanks with water. How many tanks of water will 4 students fill in one- third of an hour at the same rate? (b) A chord, 20 cm long, is 12 cm from the centre of the circle. Calculate, correct to one decimal place, the : (i) angle subtended by the chord at the centre of the circle; (ii) perimeter of the minor segment cut off by the chord. [Take ].
Explanation
(a) 4 students will take It will take 20 minutes to fill (b) (ii) Perimeter of minor segment = Length of chord + length of arc But = Length of arc = Perimeter of minor segment = 20 + 21.71 = 41.71cm