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Question
Aruna has only Rs 1 and Rs 2 coins with her. If the total number of coins that she has is 50 and the amount of money with her is Rs 75, then the number of Rs 1 and Rs 2 coins are, respectively ______.
Options
35 and 15
35 and 20
15 and 35
25 and 25
Solution
Aruna has only Rs 1 and Rs 2 coins with her. If the total number of coins that she has is 50 and the amount of money with her is Rs 75, then the number of Rs 1 and Rs 2 coins are, respectively 25 and 25.
Explanation:
Let the number of Rs 1 coins = x
And number of Rs 2 coins = y
x + y = 50 ..........(i)
Also, (x × 1) + (y × 2) = 75
⇒ x + 2y = 75 ........(ii)
On subtracting (i) from (ii), we get
y = 75 – 50
= 25
When y = 25, then from (i),
x = 25
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