Final answer:
Neetu has 26 notes of Rs 20 and 38 notes of Rs 50.
Step-by-step explanation:
Let's assume that Neetu has x number of 20-rupee notes. Since she has 12 more 50-rupee notes than 20-rupee notes, she must have (x+12) number of 50-rupee notes.
The total value of the 20-rupee notes will be 20x, and the total value of the 50-rupee notes will be 50(x+12).
According to the given condition, the total value of all the notes is Rs 1,020. So we can set up the equation: 20x + 50(x+12) = 1020.
Solving this equation will give us the value of x and x+12, which represents the number of 20-rupee notes and 50-rupee notes respectively.
After solving the equation, we find that x = 26. Therefore, Neetu has 26 20-rupee notes and (26+12) = 38 50-rupee notes.