21. Nisha bought a number of oranges at 2 for a rupee and an equal number at 3 for a rupee. To make a profit of 20% she should sell a dozen for

1. 1. $ 6

   
   
   

   2. $ 8

   
   
   

   3. $ 10

   
   
   

   4. $ 12

   
   
   

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1. View Hint View Answer Discuss in Forum

   Let Total oranges bought = 12 or dozen
   ∴ Their cost price = 3 + 2 = 5
   For profit of 20%,
   

   ∴ Selling Price =	Cost price × ( 100 + Profit% )
   	100

   
   

   Correct Option: A

   Let Total oranges bought = 12 or dozen
   ∴ Their cost price = 3 + 2 = 5
   For profit of 20%,
   

   ∴ Selling Price =	Cost price × ( 100 + Profit% )
   	100

   
   

   Selling Price =	5 × 120	= $ 6
   	100

   
   

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22. There is a profit of 20% on the cost price of an article. The % of profit, when calculated on selling price is

1. 1. 16	2	%
      	3

      
      

   
   
   

   2. 20%

   
   
   

   3. 33	1	%
      	3

   
   
   

   4. None of these

   
   
   

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1. View Hint View Answer Discuss in Forum

   Let Cost Price of article = $ y
   For Profit of 20% ,
   

   Selling Price =		120y	= $	6y
   		100		5

   
   

   Gain =		6y	- y =	6y - 5y
   		5		5

   
   

   Gain = $	y
   	5

   
   

   ∴ Gain percent =	Gain	× 100
   	Selling Price

   
   

   Correct Option: A

   Let Cost Price of article = $ y
   For Profit of 20% ,
   

   Selling Price =		120y	= $	6y
   		100		5

   
   

   Gain =		6y	- y =	6y - 5y
   		5		5

   
   

   Gain = $	y
   	5

   
   

   ∴ Gain percent =	Gain	× 100
   	Selling Price

   
   

   Gain percent =		(y / 5)	× 100 =	50
   		(6y / 5y)		3

   
   

   Gain percent = 16	2	%
   	3

   
   

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23. If selling price of an article is 1	1	of cost price, find gain %.
    	3

1. 1. 25%

   
   
   

   2. 33	1	%
      	3

      
      

   
   
   

   3. 1.33%

   
   
   

   4. 66	2	%
      	3

      
      

   
   
   

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1. View Hint View Answer Discuss in Forum

   Let Cost Price of article = y
   

   Selling Price of article = $	4y
   	3

   
   Gain = Selling Price - Cost Price
   

   Gain =		4y	- y =	4y - 3y
   		3		3

   
   

   Gain = $	y
   	3

   
   

   ∴ Gain% =	Gain	× 100
   	Cost Price

   
   

   Correct Option: B

   Let Cost Price of article = y
   

   Selling Price of article = $	4y
   	3

   
   Gain = Selling Price - Cost Price
   

   Gain =		4y	- y =	4y - 3y
   		3		3

   
   

   Gain = $	y
   	3

   
   

   ∴ Gain% =	Gain	× 100
   	Cost Price

   
   

   Gain percent =	(y / 3)	× 100
   	y

   
   

   =		100	= 33	1	%
   		3		3

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24. A merchant loses 10% by selling an article. If the cost price of the article is $ 15, then the selling price of the article is

1. 1. $ 13.20

   
   
   

   2. $ 16.50

   
   
   

   3. $ 12.30

   
   
   

   4. $ 13.50

   
   
   

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1. View Hint View Answer Discuss in Forum

   Given that , Lose = 10% and Cost price of the article = $ 15
   

   Selling price of article =	(100 – loss%)	× Cost price
   	100

   
   

   Correct Option: D

   Given that , Lose = 10% and Cost price of the article = $ 15
   

   Selling price of article =	(100 – loss%)	× Cost price
   	100

   
   

   Selling price of article =		( 100 - 10 )	× 15 =	90 × 15	= $ 13.50
   		100		100

   
   

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25. Pooja wants to sell a watch at a profit of 20%. She bought it at 10% less and sold it at $ 30 less, but still she gained 20%. The cost price of watch is

1. 1. $ 240

   
   
   

   2. $ 220

   
   
   

   3. $ 250

   
   
   

   4. $ 225

   
   
   

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1. View Hint View Answer Discuss in Forum

   Let Cost Price of watch = Rs. y
   

   ∴ Selling Price =		120y	= Rs.	6y
   		100		5

   
   Case II,
   

   Cost Price = Rs.	9y
   	10

   
   

   Selling Price = Rs.		6y	- 30
   		5

   
   According to the question,
   

   6y	- 30	=		9y	×	120
   5				10		100

   
   
   

   Correct Option: C

   Let Cost Price of watch = Rs. y
   

   ∴ Selling Price =		120y	= Rs.	6y
   		100		5

   
   Case II,
   

   Cost Price = Rs.	9y
   	10

   
   

   Selling Price = Rs.		6y	- 30
   		5

   
   According to the question,
   

   6y	- 30	=		9y	×	120
   5				10		100

   
   

   6y	- 30 =	27y
   5		25

   
   

   ⇒		6y	-	27y	= 30
   		5		25

   
   ⇒ 3y = 30 × 25
   

   ⇒ y =	30 × 25	= Rs. 250
   	3

   
   

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