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October 28th, 2018, 03:40 AM   #1
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How are 2 and 5 written?

Rohit has some 50 paisa coins, some 2 rupee coins, some 1 rupee coins and some 5 rupee coins. The value of all the coins is Rs 50. Number of 2 rupee coins is 5 more than that of the 5 rupee coins. 50 paisa coins are double in number than 1 rupee coins. Value of 50 paisa coins and 1 rupee coins is Rs 26. How many 2 rupee coins does he have?
A) 50p, 2 rupee, 1 rupee and 5 rupee
When we add all the coins, the resultant value is 50 rs.
Assume 2 rupee coin be X
Assume 5 rupee coin be X -5 because it is given 5 rupee coins is 5 less
than 2 rupee coins.
2X + 5(X-5) = 50 – total of (50p + 1rupee)
50p + 1rupee = 26 (given)
→ 2X + 5(X-5) = 50 – 26
→ 2X + 5X - 25 = 24
→ 7X = 49
→ X = 7

I highlighted the part with bold, please explain how are 2 and 5 written?
Is there any easy method to solve this ratio problem?
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October 28th, 2018, 05:59 AM   #2
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You wrote "Assume 2 rupee coin be X". If that means that the number of 2 rupee coins is X, their total value is the value of each coin multiplied by the number of coins, i.e. 2X rupees.

Your method and working are correct. You used the easiest method. Problems of this type sometimes require the use of two variables, but this was an easy problem for which one variable suffices.
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October 29th, 2018, 01:27 AM   #3
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Quote:
Originally Posted by skipjack View Post
You wrote "Assume 2 rupee coin be X". If that means that the number of 2 rupee coins is X, their total value is the value of each coin multiplied by the number of coins, i.e. 2X rupees.
Number of 2 rupee coins didn't mention in the question, how can you tell they are two 2 rupee coins?
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October 29th, 2018, 03:45 AM   #4
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The question refers to coins that are worth 2 rupees each. By "the number of 2 rupee coins is X", I meant "there are exactly X coins that are each worth 2 rupees".

In other words, "2 rupee coins" means "coins having a face value of 2 rupees". It turns out that there are 7 such coins.
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