Question

A total of 90 currency notes consisting only of 5 and 10 denominations amount to 500 find the number of notes in each denomination

Answer 1

Answer:80 and 10 respectively

Step-by-step explanation:

Answer 2

$\huge\sf{\underline{\underline{Solution:}}}$

• Let the number of Rs. 5 currencies be denoted as 'x'

• Let Rs. 10 currencies be denoted as y.

$\bold{According \:to \:the \:question,}$

⇒ x + y = 90

Also, it is given that total amount is Rs. 500.

Therefore it is given as:

⇒ 5x + 10y = Rs. 500

⇒ x + 2y = 100

Solving the equations,

⇒ x + 2y = 100

⇒ x = 100 - 2y

Substituting this in the first equation we get,

⇒ ( 100 - 2y ) + y = 90

⇒ 100 - y = 90

⇒ y = 100 - 90

⇒ y = 10

Therefore x can be found out as:

⇒ x = 100 -2y

⇒ x = 100 - 2 ( 10 )

⇒ x = 100 - 20

⇒ x = 80