self Maths Puzzle

If a person have coins of only two denominations (among 5,20,25,50 paisa),in such a way that if quantity of one denomination is multiplied by its value and again multiplied by 4, it's equal to the amount obtained when other denomination coin is multiplied by its value. Find these two types of coins.

Read Solution (Total 3)

Answer is 25 and 50.
25*25*4=2500 and
50*50=2500 thus the above condition is satisfied.

If we take 5, 20
5*5*4=100
20*20=400
thus it couldn't be the anwer. ;)
cheers
12 years agoHelpfull: Yes(4) No(1)

25 paisa and 50 paisa

If these two coins are of denominations D and d , then
d*d*4 = D*D
D^2 = 4d^2
D=2d

From available combinations, only possible case when
d=25 paisa and D = 50 paisa
12 years agoHelpfull: Yes(2) No(1)
Ans. : These coins are of 5 paisa and 20 paisa.

Explanation:
If there are x coins of each type, then
then value of x coins of 5 paisa is = 5*x
Now as per given condition
5x * 4 = 20*x which is value of x coins of 20 paise.
12 years agoHelpfull: Yes(0) No(3)

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