Maths Question

a)2700 = k + 35(60)
k = 600
b)C = 600 + 35n
C = 600 + 35(80)
C = 3400
the average cost of making a ball = 3400/80 =$42.5
c) 80 balls are made cost $3400
selling make profit = $90 * (80*85% * (1-15%) + 80*15% * 50%) - $3400
= $2342
profit % = 2342/3400 =68.9%(3 sig. fig.)

a) 2700 = k + 35(60)
k = 600

b) C = 600+35(80)
C = $3400
Average cost = C/80 = 3400/80 = $42.5

c) sold at 15% discount balls' total price = [90*(1-15%)]*[80*0.85] = $5202
sold at half price balls' total price = [90*0.5]*[80*0.15] = $540
profit percentage = [(5202+540) - 3400 / 3400] X 100% = 68.9% (corr to 3 sig. fig.)

a.
2700=k+35(60)
k=2700-35(60)
k=600

b.
The total cost of making 80 balls
=600+35(80)
=$3400

The average cost of making a ball
=$3400/80
=$42.5

c.
The profit of of selling 80 balls
=$908085%(1+15%)+$9080(1-85%)/2
=$720085%(1+15%)+$7200(1-85%)/2
=$7038+$540
=$7578

The total cost of making 80 balls=$3400

The profit percentage of making and selling 80 balls
=($7578-$3400)/$3400100%
=123%, cor. to 3 sig. fig.

2009-12-24 17:52:08 補充：
更正：
c.
The total cost of making 80 balls=$3400

The profit of of selling 80 balls
=$90*80*85%*(1-15%)+$90*80*(1-85%)/2-$3400
=$7200*85%*(1-15%)+$7200*(1-85%)/2-$3400
=$5202+$540-$3400
=$2342

The profit percentage of making and selling 80 balls
=$2342/$3400*100%
=68.9%, cor. to 3 sig. fig.