Name : ____________________    Date   : _____________

                                                          Score : _____________

Write down your correct answer and show your workings:

  1)  Andrew had $268 and Brett had $172 at first. 
       Each of them bought a pair of skates at the same price. 
       After their purchase, Andrew had 5 times as much money left as Brett. 
       How much did each pair of skates cost? 
 
 
 
 
 
 
 
 
 
 
 
 

    Ans: ____________________
 

  2)  540 trees are to be planted along the perimeter of a square garden
       so that there will be an equal number of trees along each side of the garden. 
       How many trees must be planted along each side of the garden?
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

    Ans: ____________________
 

  3) Tan bought some mangoes and apples for $86.50. 
      A mango and an apple cost $11 in all. 
      He bought more mangoes than apples and the mangoes cost $42.50 more. 
      How many apples did he buy?
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

    Ans: ____________________
 

  4) Pail A contained 7/17 of the amount of water in Pail B. 
      Pail C contained 1/9 of the total amount of water the three pails had. 
      If Pail A and Pail B contained 5.25 litres of water more than Pail C, 
      how much water did Pail B contain? (give the answer in litres)?
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

    Ans: ____________________
 

  5) 100 workers were paid a total of $24750. 
      If 25% of them received 20% more money than the remaining men, 
      calculate the amount received by each man from the group who got less.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

    Ans: ____________________
 
 

Answers:

  1) You may use UM (Units Method) or MD.

      Andrew and Brett bought a pair of skates at the same price.
      The difference between Andrew’s initial amount and Brett’s initial amount remains the same.

      After the purchase

      Andrew ------- 5 units (Andrew had 5 times as much money left as Brett)
      Brett ------- 1 unit
      Difference ------ 4 units

      268 -172 = 96

      4 units = 96
      1 unit   = 96 / 4 = 24

     Cost of a pair of skates = 172 - 24 = 148

  2) Assuming that one tree is planted at each corner of the square garden. 
      This gives us 4 trees at 4 corners. 
      It helps to draw a simple diagram.

       540 - 4 = 536

       536/4 = 134

       134 + 2 = 136

  3) You may use “Grouping Concept”.

       86.5 – 42.5 = 44

       Consider a group of 1 mango and 1 apple that costs $11

       44/11 = 4

      There are 4 groups.

      Hence, 4 apples

  4) Pail A = 7 units
      Pail B = 17 units

      Multiples of 9 ------- 9, 18,27 ………

     1/9 * 27 = 3 units

     Pail C = 3 units.

     24 units – 3 units = 21 units

     21units =  5.25

    1 unit = 0.25

     Pail B = 17 * 0.25 = 4.25 litres

     Notes:
     Why use multiple of 9 and why is 27 chosen instead of other numbers like 18

     C contained 1/9 of the total amount of water the three pails had.
     Hence, we use multiples of 9, just to make the calculations easier.

     The number of units for Pail A and Pail B add up to 24 (7+17).

     Hence the total number of units (A+B+C) has to be greater than 24.

     Alternatively, you may use MD.

     7 units (Pail A) +17 units (Pail B) + 1 part (Pail C) = 9 parts (representing A+B+C)

     24 units = 8 parts

     3 units = 24/8 = 1 part

  5) 25% = 25 workers
      75% = 75 workers

     The lower wage worker receives 1 unit each

     75 units + 90 units (20% more) = 24750
     165 units = 24650

     1 unit = 150

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