Question:Find the average of £1.34, £4.16 and £5.81
Answer
£1.34+£4.16+£5.81 = £11.31 The average=`(£11.31)/3`= £3.77
Question:Find the average of £1.34, £4.16 and £5.81
£1.34+£4.16+£5.81 = £11.31 The average=`(£11.31)/3`= £3.77
Question:Find the average of x+y, 2x+3y, 2x-2y and 3x-2y
(x+y)+(2x+3y)+(2x-2y)+(3x-2y) = x+2x+2x+3x+y+3y-2y-2y = 8x The average = `8x/4`= 2x
Question:I buy 8 kg of cooking apples at 10p per kg and 2 kg of eating apples at 15p per kg. Find the average cost of 1 kg of apples.
8 kg at 10p per kg cost 80 new pence 2 kg at 15p per kg cost 30 new pence Total cost of 10 kg is 110 new pence The average cost per kg is `110/10` = 11p.
Question:A merchant blends two brands of tea costing 60 new pence per kg an d80 new pence per kg in ratio 3:1. What is the cost of 1 kg of the mixture?
Suppose he mixes 3 kg of 60p tea with 1 kg of 80p tea. Cost of 3 kg at 60p per kg is 180 new pence Cost of 1 kg at 80p per kg is 80 new pence Total cost of 4 kg of tea is 260 new pence Average cost per kg is 65 new pence.
Question:A boy cycles 10 km at 15 km/h and a further 20 km at 20 km/h. Find his average speed over the whole journey.
The time taken to go d k at v km/h. = `d/v` hours. The time taken to cycle 10 km at 15 km/h. = `10/15` = `2/3` hour. The time taken to cycle 20 km at 20 km/h. = `20/20` = 1 hour. The total time taken to cycle 30 km = `1 2/3` hours. The average speed = distance gone/time taken = `30/(1 2/3) = 90/5 = 18 km/h`