Question

15. I have a total of ₹ 300 in coins of denomination ₹1, ₹2 and ₹5. The
number of ₹2 coins is 3 times the number of ₹5 coins. The total number of
coins is 160. How many coins of each denomination are with me?
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Answer 1

Step-by-step explanation:

ANSWER:-

GIVEN:-

300 coins of Denomination Rs. 1, 2 and 5.

Let the number of Rs. 5 coins be x. ( Reason Explained below)

ATQ,

Rs. 2 coins will be 3x.

Total Coins given = 160

So, Rs. 1 will be

160-(3x+x)

= 160-4x for Rs.1

Rs. 2 = 2(3x)

Rs. 2 = 6x

Rs.5 = 5(x)

Rs. 5 = 5x

Totaling All,

5x+6x+160-4x = 300

5x + 6x + 160 - 4x = 300

11x - 4x + 160 = 300

7x = 140

x = 20

• Rs. 5 coins is 20
• Rs 2 coins is 20×3 = 60
• Rs 1 coins is 160 - 4(20) = 80

Reason:-

• Whenever a base factor is given then we take it as a constant.
• x as a constant to base factor 5.

Answer 2

Let the number of ₹5 coins be x.

Then,

number ₹2 coins = 3x

and, number of ₹1 coins = (160 – 4x) Now,

Value of ₹5 coins = x × 5 = 5x

Value of ₹2 coins = 3x × 2 = 6x

Value of ₹1 coins = (160 – 4x) × 1 = (160 – 4x)

According to the question,

5x + 6x + (160 – 4x) = 300

⇒ 11x + 160 – 4x = 300

⇒ 7x = 140

⇒ x = 140/7

⇒ x = 20

Number of ₹5 coins = x = 20

Number of ₹2 coins = 3x = 60

Number of ₹1 coins = (160 – 4x) = 160 – 80 = 80