Finding the Fourth Proportional to 31,419.92, 47,128.65 and 10,643.42

Step by Step Solution

1. Step 1: Write the proportion equation
   31,419.92 : 47,128.65 = 10,643.42 : x
2. Step 2: Convert to fraction form
   31,419.92/47,128.65 = 10,643.42/x
3. Step 3: Cross multiply
   31,419.92x = 47,128.65 × 10,643.42
4. Step 4: Simplify right side
   31,419.92x = 501,610,015.98
5. Step 5: Solve for x
   x = 501,610,015.98/31,419.92
6. Step 6: Final answer
   x = 15,964.71