Scroll:Whole Numbers >> Other Heuristics >> ps (301)

Written Instructions:

For each Multiple Choice Question (MCQ), four options are given. One of them is the correct answer. Make your choice (1,2,3 or 4). Write your answers in the brackets provided..

For each Short Answer Question(SAQ) and Long Answer Question(LAQ), write your answers in the blanks provided.

Leave your answers in the simplest form or correct to two decimal places.


 

1)  

There are some coins in a box. The coins consist of 10-cent and 20-cent coins. There are twice as many 10-cent coins as 20-cent coins. If the total amount of money in the box is 20, how many coins are there together


Answer:_______________




2)  

There are some coins in a box. The coins consist of 10-cent and 20-cent coins. There are thrice as many 10-cent coins as 20-cent coins. If the total amount of money in the box is 39, how many coins are there together


Answer:_______________




3)  

Selvanayaki had a total of 180, consisting of 10 and 2 notes. Given that she had five times as many 2 notes as 10 notes, how many notes did she have


Answer:_______________




4)  

Thamarai had a total of 208, consisting of 10 and 2 notes. Given that she had three times as many 2 notes as 10 notes, how many notes did she have


Answer:_______________




5)  

Barathan had a total of 54, consisting of 10 and 2 notes. Given that he had four times as many 2 notes as 10 notes, how many notes did he have


Answer:_______________




6)  

There are some coins in a box. The coins consist of 10-cent and 20-cent coins. There are four times as many 10-cent coins as 20-cent coins. If the total amount of money in the box is 42, how many coins are there together


Answer:_______________




7)  

There are some coins in a box. The coins consist of 10-cent and 20-cent coins. There are twice as many 10-cent coins as 20-cent coins. If the total amount of money in the box is 16, how many coins are there together


Answer:_______________




8)  

There are some coins in a box. The coins consist of 10-cent and 20-cent coins. There are thrice as many 10-cent coins as 20-cent coins. If the total amount of money in the box is 13, how many coins are there together


Answer:_______________




9)  

Ramani had a total of 240, consisting of 10 and 2 notes. Given that she had five times as many 2 notes as 10 notes, how many notes did she have


Answer:_______________




10)  

Amutha had a total of 80, consisting of 10 and 2 notes. Given that she had three times as many 2 notes as 10 notes, how many notes did she have


Answer:_______________




 

1)  

There are some coins in a box. The coins consist of 10-cent and 20-cent coins. There are twice as many 10-cent coins as 20-cent coins. If the total amount of money in the box is 20, how many coins are there together

Answer: 150


SOLUTION 1 :

Grouping method

Step 1:

0.20 + 0.10 + 0.10 = 0.40(1 set)

Step 2:

20 ÷ 0.40 = 50 sets

*Note: 1 set has 3 notes

Step 3:

50 x 3 = 150 


SOLUTION 2 :
  No. of coins x Value Total Value
10-cent 2u x 0.10 0.20
20-cent 1u x 0.20 0.20
  3u     0.40

Step 1:

  20 ÷ 0.40 = 50

Step 2:

2 units (10-cent) + 1 unit (20-cent) = 3 units

3 units = 3 x 50

           =  150



2)  

There are some coins in a box. The coins consist of 10-cent and 20-cent coins. There are thrice as many 10-cent coins as 20-cent coins. If the total amount of money in the box is 39, how many coins are there together

Answer: 312


SOLUTION 1 :

Grouping method

Step 1:

0.20 + 0.10 + 0.10 + 0.10 = 0.50(1 set)

Step 2:

39 ÷ 0.50 = 78 sets

*Note: 1 set has 4 notes

Step 3:

78 x 4 = 312 notes


SOLUTION 2 :
  No. of coins x Value Total Value
10-cent 3u x 0.10 0.30
20-cent 1u x 0.20 0.20
  4u     0.50

Step 1:

$39 ÷ 0.50 = 78

Step 2:

3 units (10-cent) + 1 unit (20-cent) = 4 units

4 units = 4 x 78

           =  312



3)  

Selvanayaki had a total of 180, consisting of 10 and 2 notes. Given that she had five times as many 2 notes as 10 notes, how many notes did she have

Answer: 54


SOLUTION 1 :

Grouping method

Step 1:

10 + 2 + 2 + 2 + 2 + 2= 20 (1 set)

Step 2:

180 ÷ 20 = 9 sets

*Note: 1 set has 6 notes

Step 3:

9 x 6 = 54 notes


SOLUTION 2 :
  No.of notes x Value Total Units
10 1 x 10 10U
2 5 x 10 10U
  6     20U

 

Step 1:

20 units = 180

1 unit = 180  ÷ 20

          = 9

Step 2:

5 units (2 notes) + 1 unit (10 notes) = 6 units

6 units = 6 x 9

            = 54 notes



4)  

Thamarai had a total of 208, consisting of 10 and 2 notes. Given that she had three times as many 2 notes as 10 notes, how many notes did she have

Answer: 52


SOLUTION 1 :
  No.of notes x Value Total Value
10 1u x 10 10U
2 3u x 2 6U
  4u     16U

 

Step 1:

16 units = 208

1 unit = 208  ÷ 16

          = 13

Step 2:

3 units (2 notes) + 1 unit (10 notes) = 4 units

4 units = 4 x 13

            = 52 notes


SOLUTION 2 :

Grouping method

Step 1:

10 + 2 + 2 + 2 = 16(1 set)

Step 2:

208 ÷ 16 = 13 sets

*Note: 1 set has 4 notes

Step 3:

13 x 4 = 52 notes



5)  

Barathan had a total of 54, consisting of 10 and 2 notes. Given that he had four times as many 2 notes as 10 notes, how many notes did he have

Answer: 15


SOLUTION 1 :
  No.of notes x Value Total Units
10 1u x 10 10U
2 4u x 2 8U
  5u     18U

 

Step 1:

18 units = 54

1 unit = 54  ÷ 18

          = 3

Step 2:

4 units (2 notes) + 1 unit (10 notes) = 5 units

5 units = 5 x 3

            = 15 notes


SOLUTION 2 :

Grouping method

Step 1: 10 + 2 + 2 + 2 + 2 = 18(1 set)

Step 2: 54 ÷ 18 = 3 sets

*Note: 1 set has 5 notes

Step 3: 3 x 5 = 15 notes



6)  

There are some coins in a box. The coins consist of 10-cent and 20-cent coins. There are four times as many 10-cent coins as 20-cent coins. If the total amount of money in the box is 42, how many coins are there together

Answer: 350


SOLUTION 1 :
  No. of coins x Value Total Value
10-cent 4u x 0.10 0.40
20-cent 1u x 0.20 0.20
  5u     0.60

Step 1:

42 ÷ 0.60 = 70

Step 2:

4 units (10-cent) + 1 unit (20-cent) = 5 units

5 units = 5 x 70

            =  350


SOLUTION 2 :

Grouping method

Step 1:

0.20 + 0.10 + 0.10 + 0.10 + 0.10 = 0.60(1 set)

Step 2:

42 ÷ 0.60 = 70 sets

*Note: 1 set has 5 notes

Step 3:

70 x 5 = 350 notes



7)  

There are some coins in a box. The coins consist of 10-cent and 20-cent coins. There are twice as many 10-cent coins as 20-cent coins. If the total amount of money in the box is 16, how many coins are there together

Answer: 120


SOLUTION 1 :

Grouping method

Step 1:

0.20 + 0.10 + 0.10 = 0.40(1 set)

Step 2:

16 ÷ 0.40 = 40 sets

*Note: 1 set has 3 notes

Step 3:

40 x 3 = 120 


SOLUTION 2 :
  No. of coins x Value Total Value
10-cent 2u x 0.10 0.20
20-cent 1u x 0.20 0.20
  3u     0.40

Step 1:

  16 ÷ 0.40 = 40

Step 2:

2 units (10-cent) + 1 unit (20-cent) = 3 units

3 units = 3 x 40

           =  120



8)  

There are some coins in a box. The coins consist of 10-cent and 20-cent coins. There are thrice as many 10-cent coins as 20-cent coins. If the total amount of money in the box is 13, how many coins are there together

Answer: 104


SOLUTION 1 :

Grouping method

Step 1:

0.20 + 0.10 + 0.10 + 0.10 = 0.50(1 set)

Step 2:

13 ÷ 0.50 = 26 sets

*Note: 1 set has 4 notes

Step 3:

26 x 4 = 104 notes


SOLUTION 2 :
  No. of coins x Value Total Value
10-cent 3u x 0.10 0.30
20-cent 1u x 0.20 0.20
  4u     0.50

Step 1:

$13 ÷ 0.50 = 26

Step 2:

3 units (10-cent) + 1 unit (20-cent) = 4 units

4 units = 4 x 26

           =  104



9)  

Ramani had a total of 240, consisting of 10 and 2 notes. Given that she had five times as many 2 notes as 10 notes, how many notes did she have

Answer: 72


SOLUTION 1 :

Grouping method

Step 1:

10 + 2 + 2 + 2 + 2 + 2= 20 (1 set)

Step 2:

240 ÷ 20 = 12 sets

*Note: 1 set has 6 notes

Step 3:

12 x 6 = 72 notes


SOLUTION 2 :
  No.of notes x Value Total Units
10 1 x 10 10U
2 5 x 10 10U
  6     20U

 

Step 1:

20 units = 240

1 unit = 240  ÷ 20

          = 12

Step 2:

5 units (2 notes) + 1 unit (10 notes) = 6 units

6 units = 6 x 12

            = 72 notes



10)  

Amutha had a total of 80, consisting of 10 and 2 notes. Given that she had three times as many 2 notes as 10 notes, how many notes did she have

Answer: 20


SOLUTION 1 :
  No.of notes x Value Total Value
10 1u x 10 10U
2 3u x 2 6U
  4u     16U

 

Step 1:

16 units = 80

1 unit = 80  ÷ 16

          = 5

Step 2:

3 units (2 notes) + 1 unit (10 notes) = 4 units

4 units = 4 x 5

            = 20 notes


SOLUTION 2 :

Grouping method

Step 1:

10 + 2 + 2 + 2 = 16(1 set)

Step 2:

80 ÷ 16 = 5 sets

*Note: 1 set has 4 notes

Step 3:

5 x 4 = 20 notes