Finding the Fourth Proportional to 42,931.95, 64,085.21 and 39,766.12

Step by Step Solution

1. Step 1: Write the proportion equation
   42,931.95 : 64,085.21 = 39,766.12 : x
2. Step 2: Convert to fraction form
   42,931.95/64,085.21 = 39,766.12/x
3. Step 3: Cross multiply
   42,931.95x = 64,085.21 × 39,766.12
4. Step 4: Simplify right side
   42,931.95x = 2,548,419,952.25
5. Step 5: Solve for x
   x = 2,548,419,952.25/42,931.95
6. Step 6: Final answer
   x = 59,359.53