Solution:

Here,
SP with VAT = Rs 9040
Discount percentage (d%) = 20%
VAT % = 13%

To find: Marked Price (MP) = ?

We know,
SP = $\dfrac{SP with VAT}{100 + \frac{VAT%}{100}}$

$= \dfrac{9040}{100 + \frac{13}{100}}$

$= 9040 × \dfrac{100}{113}$

$= Rs 8000$


Now,
Marked Price (MP) = $\dfrac{SP}{1 - \frac{d%}{100}}$

$= \dfrac{8000}{1 - \frac{20}{100}}$

$= \dfrac{8000}{\frac{80}{100}}$

$= 8000 × \frac{100}{80}$

$= Rs 10000$


Hence, the required marked price of the bicycle is Rs 10,000.