Finding the Fourth Proportional to 42,963.55, 64,440.52 and 13,378.91

Step by Step Solution

1. Step 1: Write the proportion equation
   42,963.55 : 64,440.52 = 13,378.91 : x
2. Step 2: Convert to fraction form
   42,963.55/64,440.52 = 13,378.91/x
3. Step 3: Cross multiply
   42,963.55x = 64,440.52 × 13,378.91
4. Step 4: Simplify right side
   42,963.55x = 862,143,561.78
5. Step 5: Solve for x
   x = 862,143,561.78/42,963.55
6. Step 6: Final answer
   x = 20,066.86