Question

aravind has a kiddy bank it is full of one rupee and fifty paise coins. it contains 3 times as many fifty paise coins as one rupee coins. the total amount of the money in the bank is rs 35.
how many coins of each kind in the bank ?

Answer 1

Answer:
      let number of one rupee coins = x
therefore , number of 50 paisa coins = 3x
Total amount of money = Rs 35
therefore ,
   0.5(3x) + 1(x) = 35
.15x +1x= 35
or 25/10x=35
or 25x= 35*10
or 25x =350
or x= 14
Therefore , Number of one Rupee coins = 12
Hence Number of 50 paisa coins = 3*14 = 42

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Answer 2

Let no. of one rupee coins be x = 1 * x = x
               fifty paise coins = 3x = 3 * 50x/100 = 15x/10
  
A.T.Q

x  + $\frac{15x}{10}$ = 35 
$\frac{10x}{10}$ + $\frac{15x}{10}$ = 35               (LCM=10)
$\frac{25x}{10}$ = 35
25x = 35 * 10
x = $\frac{350}{25}$
x = 14

no. of 1 rupee coin = x = 14
no. of 50 paise coin = 3x = 14 * 3 = 42