Question

Question no 13 of liner equation

Answer 1

Hi there !!

Total sum of denominations = Rs 800

Total number of notes = 50

Let Rs 10 Notes be x

Rs 20 notes = 50 - x

Since the total sum of denominations is given in Rs, we have to find the total value of RS 10 and Rs 20 notes

So,

Value of :

Rs 10 notes = 10(x) = 10x Rs


Rs 20 notes = 20(50-x) = 1000 - 20x Rs


Further,
the following balanced equation will be formed:


$10x + 1000 - 20x = 800$


$- 10x + 1000 = 800$
Transposing 1000 to. RHS ,
we have,

$- 10x = 800 - 1000$

$- 10x = - 200$
Since , both the LHS and the RHS have the same signs ie, minus sign ,
both of them will become positive


$10x = 200$

$x = \frac{200}{10}$
x = 20

So,

Rs 10 notes = x = 20

Rs 20 notes = 50-x = 50 -20 = 30


Thus,
there are 20 notes of RS 10 and 30 notes of Rs 20

Answer 2

Hi,

Please see the attached file!


Thanks