Explanation:

To solve the problem, let's define the following variables:

- Let the number of Rs10 coins be $x$.

- Then, the number of Rs5 coins is $x+8$.

- The number of Rs2 coins is 20% more than Rs5 coins so that’s $\frac{5}{4}(x+8)$.

Given, the total amount in the bag is Rs270. Then the equation for the total value is:

- $10x+5(x+8)+2\times \frac{5}{4}(x+8)=270$.

Solving the equation:

1. Simplify inside parentheses:

$\frac{5}{4}(x+8)=\frac{5x}{4}+10$.

2. Substitute and solve:

$10x+5x+40+\frac{5x}{2}+20=270$.

3. Combine like terms:

$15x+\frac{5x}{2}+60=270$.

4. Convert to a single denominator:

$30x/2+5x/2=210$.

5. Combine terms:

$35x/2=210$.

6. Solve for $x$:

$35x=420$,

$x=12$.

- Therefore, Rs5 coins = $x+8=20$.

So, the number of Rs5 coins is:

- Option: 2, 20