Question

Shama has some ₹ 2 and some ₹ 5 coins. The total number of coins are 50 and their total cost is ₹ 190. Find the number of ₹ 2 coins and of ₹ 5 coins.

Answer 1

Given:

• Total number of coins = 50
• Coins of ₹ 2 and ₹ 5 only
• Total amount = ₹ 190

Let the number of ₹ 2 coins be x.

Then the number of ₹ 5 coins = 50 – x.

Step-wise calculation:

1. Total coins equation:

x + (50 – x) = 50

2. Total amount equation:

2x + 5(50 – x) = 190

3. Simplify the amount equation:

2x + 250 – 5x = 190 

–3x + 250 = 190 

–3x = 190 – 250 

–3x = –60

`x = (-60)/(-3)`

x = 20

4. Number of ₹ 5 coins:

50 – x = 50 – 20

50 – x = 30

Number of ₹ 2 coins = 20.

Number of ₹ 5 coins = 30.