F.1Maths

2.A hawker bought 360 eggs which originally cost $0.5each at a discount of 20%. He threw away 40rotten eggs.Then he sold 250 eggs at a marked price of $0.6 each and the rest at a discount of 20% on the marked price.Find
(a)the total cost of the eggs,

Total cost of the eggs

= 360 * $0.5 * (1-20%)

= $360 * 0.5 * 80%

= $360 * 0.5 * 0.8

= $144

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(b)the total selling price,

Income of selling 250 eggs at $0.6

= 250 * $0.6

= $150

Income of selling the rest at discount of 20%

= (360 - 40 - 250) * $0.6 * (1-20%)

= $70 * 0.6 * 80%

= $70 * 0.6 * 0.8

= $33.6

Total income

= $150 + $33.6

= $183.6

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(c)the profit per cent

The profit percent

= ($183.6 - $144)/$144 * 100%

= 39.6/144 * 100%

= 27.5%

(a) The total cost of the eggs
$0.5*(1-20%)*360
=$144

(b)The total selling price
$0.6*250+$0.6*(1-20%)*(360-40-250)
=$150+$33.6
=$183.6

(c)The profit percent
(183.6-144)/144
=27.5%

2a) The total cost of the eggs=

$0.5 * 360 * (1-20%)

=$0.5 * 360 * 80%

=$0.5 * 360 * 80 / 100

=$144

2b) The total selling price=

$0.6 * 250 + $0.6 * (360 - 40 - 250) * (1 - 20%)]

=$0.6 * 250 + $0.6 * 70 * 80%

=$0.6 * 250 + $0.6 * 70 * 80 / 100

=$150 + $33.6

=$183.6

2c) The profit percent=

($183.6 - $144) / $144 * 100%

= 39.6 / 144 * 100%

= 0.275 * 100%

= 27.5%

2007-01-02 22:50:42 補充：
2b)He sold 250 eggs at a marked price of $0.6 each:$0.6 * 250And the rest at a discount of 20% on the marked price:$0.6 * (360 - 40 - 250) * (1 - 20%)所以係 $0.6 * 250 ＋ $0.6 * (360 - 40 - 250) * (1 - 20%)後面多左個"]"係唔要的