Q. A bag contains a total of 90 coins in the form of 20 paise and 25 paise coins. If the total value of coins in the bag is Rs.21, find the no of 25 paise coins in the bag?

Option
a) 60
b) 55
c) 65
d) 70

• The best way of solving the question is assuming all the coins to be 25 paise coins,so total amount should be Rs. 18( 90 *20). But in reality, the amount is Rs.21.
  The reason for that extra 300 paise is , some of the coins are 25 paise insted of 20 paise. Each 25 paise coin is 5 more than 20 paise coin. To get 300 paise more, there should be 300/5 = 60 coins.
  There should be 60 25 paise coins.
  
• 10 years agoHelpfull: Yes(6) No(4)
• Ans :- 60
  
  20x+25y=2100................(i)
  x+y=90.............................(ii)
  solving i & ii
  y=60
• 9 years agoHelpfull: Yes(5) No(4)
• 2100 rupees
  if all coin is 20 paise then 90*20=1800
  
  rest will we 300 paise
  So that Number of 20 paise is replaced by 25 paisa by increment by 5 paise = 300/5=60 coin of 25 paise
  
• 8 years agoHelpfull: Yes(3) No(2)
• The simplest way to solve this question can be by looking at the options given,
  we know that 4, 25p coins make 1 rupees(4*25), what we do is we simply divide the options by 4 whichever gets divided will be the answer. In this case- 60 coins of 25p.
• 7 years agoHelpfull: Yes(0) No(2)
• Let 20 paise = X
  25 paise = 90-x
  20*(X) + 25 * (90-x) = 21*100(to make 21 RS. As paise multiply by 100)
  X= 30
  Put it into the above equation 25= 90-(30)
  25 paise = 60 coins .
• 5 years agoHelpfull: Yes(0) No(0)