Solution:

Here,

Marked Price (MP) = Rs 40 000

SP with VAT = Rs 36 160

VAT% = 30%

To find: discount percentage (d%) = ? and discount amount (d) = ?

We know,

SP = $\dfrac{\text{SP with VAT}}{1 + \dfrac{VAT%}{100}}$

$= \dfrac{40 000}{1 + \dfrac{30}{100}}$

$= Rs 30769.23$

And,

Discount (d) = MP - SP

$= 40 000 - 30769.23$

$= Rs 9230.77$

Again,

Discount percentage (d%) = $\dfrac{d}{MP}*100$

$= \dfrac{9230.77}{40000}*100$

$= 23.07%$

Hence, the required discount percentage is 23.07% and discount amount is Rs 9230.77.