A box has 210 coins of denominations one-rupee and fifty paise only. The ratio of their respective values is 13 : 11. The number of one-rupee coin is

If you convert paise into rupee how can you multiply by 2 ? it should be 11/2. it means 50/50 paise make one rupee or one coin.

rupee 13 : 0.50 paisa 11
first the unit must be same for ratio so we convert paisa into rupee; 11*2 = 22
Now 13 : 22 both rupees

Now 13x + 22x = 210 (if we multiply with x we get same no but we don't know x yet)
35x = 210
x = 6
Now 13x = 13 (6) = 78 Ans

2 nos of 50 paisa is 1 rupee likewise 1 nos of 1 rupee is 1 rupee
:.-13*(1)
11*(2)

Let,, 1 paisa rupee and .50 poisa rupee are x respectively
ATQ
13x*1+11x/.5=210
X=210/35
=>13*210/35=78

50paisa 2
Two 5oty paisa make one rupee ms

11 is multipled by 2 because 11 is paisha not rupee.after multiplying 11 has become rupee

The above question is wrong
Explanation:the given ratio is not possible for Given 210 coins

Take to consider above explanation
1 rupee coins have 78=78rupees
Renaming
210-78=132
Therefore ,50 paise coins have 132
78 and 132 are not in the given ratio (13:11)

Total coins-210
Rupee:paise
13:11(11×2=22 convert into Rs.)
We have to calculate number of one rupee coin
Here. 13(ratio of rupee)×210(total coins)÷35(13+22 rupee numbers)
=78

please explain properly its fully ???????

Ratio of 2 values must have same unit ..so we multiplied by 2 we get RS .
13:22
13x+22x=35x

Hence,no'of 1 rupee coins
13÷35×210=78

And,no'of 50 paise conis
22÷35×210=132

Cross check
132+78=210Rs

This is not the correct method of this because I don't understand why 11 is multiplied by 2???

Please explain this question

i didnt understand the formula

The solution is completely hypothetical.. Why we need to multiply 50 paise coin value by 2
13x+11x=210
24x=210
x=8.75
then 13*8.75=113.75~114 coins (But not expecting decimal points). Actually question is completely wrong.
A ratio can be applied between any types of different entities whom having same factors. But multiplying the ratio value to match the entity, is not a proper method. I again say review the question

@sailent ratio of two values must have same unit. so inorder to make 50paise into rupee we multiply by 2 (2*50paise = 1rupee)

Question just asked about number of one rupee coine then why 11*2?

to make 50 paise to 1 re.we multiply 11*2

Why multiply 11*2 I don't understand please anybody help me