Question

Reena has coins in the denominations of Rs.2, Rs.5 and Rs.10. The number of Rs.2 coins is three times the number of Rs.5 coins and total number of coins is 160. If the total amount of the coins is Rs.730, how many coins of each denomination does Reena have?

Answer 1

Answer:

30 Rs 5 coins, 90 Rs 2 coins and 40 Rs 10 coins

Step-by-step explanation:

Define x:

Let x be the number of Rs 5 coins

Rs 5 coins = x

The number of Rs 2 coins is three times the number of Rs 5 coins

Rs 2 coins = 3x

The rest are Rs 10 coins

Rs 10 coins = 160 - 3x - x

Rs 10 coins = 160 - 4x

Solve x:

Total amount is Rs 730

5x + 2(3x) + 10(160 - 4x) = 730

5x + 6x + 1600 - 40x = 730

29x = 870

x = 870 ÷ 29 = 30

Find the number of coins of each denomination:

Rs 5 = x = 30

Rs 2 = 3x = 3(30) = 90

Rs 10 = 160 - 30 - 90 = 40

Answer: There are 30 Rs 5 coins, 90 Rs 2 coins and 40 Rs 10 coins.

Answer 2

Solutions :-


Let the number of Rs 5 coins be x
Number of Rs 2 coins = 3x
Total number of coins = 160
So,
Number of Rs 10 coins = 160 - 4x
The total amount of the coins = Rs 730


A/q

=> 5(x) + 2(3x) + 10(160 - 4x) = 730
=> 5x + 6x + 1600 - 40x = 730
=> 11x - 40x = 730 - 1600
=> -29x = -870
=> x = -870/-29 = 30


Hence,
Number of Rs 5 coins = x = 30
Number of Rs 2 coins = 3x = 30 × 3 = 90
Number of Rs 10 coins = (160 - 4x) = 160 - 4×30 = 160 - 120 = 40