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NO.1 Mr.Cheng sold a van for $212 500 and made a loss of $37 500. Find the percentage loss.37500/(37 500+212500)X100%
=-15%so, percentage loss=15%
No.2 Kenneth buys a dozen of pencils for $36 and sells them at a profit of 40%. What is the selling price of each pencil?each pencil
36X(1+40%)/12
=$4.2
No.3 The cost of 10 dozens of eggs is $60. If half of the eggs are sold at a profit of 50%, and the rest are sold at a profit of 30%, find the profit from selling all the eggs.profit
30X(1+50%)+30X(1+30%)-60
=$24percentage profit
[30X(1+50%)+30X(1+30%)-60]/60X100%
=(45+39-60)/60X100%
=40%
No.4 A car is sold for $120 000 at a profit of 25%. Find the cost of the car.cost
120000X(1+25%)
=$150000
No.5 A model ship is sold for $225 at a loss 25%. How much does it cost?cost
225X(1-25%)
=$168.75

1. 37500 / (212500 + 37500) x 100%
= 37500 / 250000 x 100%
= 15%

2. 36 x (1+40%) / 12
= 50.4 / 12
= 4.2

3. 60/10 x 5 x (1+50%) + 60/10 x 5 x (1+30%) - 60
= 45 + 39 - 60
= 24

4. 120000 / (1+25%)
= 96000

5. 225 / (1-25%)
= 300