25% of annual salary of A is equal to eighty percent of annual salary of B. Monthly salary of B is 40% of the monthly salary of C. Annual salary of C is Rs. 6 lac. What is the monthly salary of A?

Sure, let's solve this step by step:

Step 1: First, we need to find the annual salary of B. We know that the annual salary of C is Rs. 6 lac. Since the monthly salary of B is 40% of the monthly salary of C, the annual salary of B (which is 12 times the monthly salary) will also be 40% of the annual salary of C. So, the annual salary of B = 40% of Rs. 6 lac = 0.40 * 6 lac = Rs. 2.4 lac.

Step 2: Now, we know that 25% of the annual salary of A is equal to 80% of the annual salary of B. So, we can set up the equation 0.25 * A = 0.80 * 2.4 lac. Solving for A, we get A = (0.80 * 2.4 lac) / 0.25 = Rs. 7.68 lac.

Step 3: Finally, we need to find the monthly salary of A. Since there are 12 months in a year, the monthly salary of A = annual salary of A / 12 = Rs. 7.68 lac / 12 = Rs. 64,000.

So, the monthly salary of A is Rs. 64,000.