Finding the Fourth Proportional to 31,978.87, 47,978.93 and 14,207.06

Step by Step Solution

1. Step 1: Write the proportion equation
   31,978.87 : 47,978.93 = 14,207.06 : x
2. Step 2: Convert to fraction form
   31,978.87/47,978.93 = 14,207.06/x
3. Step 3: Cross multiply
   31,978.87x = 47,978.93 × 14,207.06
4. Step 4: Simplify right side
   31,978.87x = 681,639,692.71
5. Step 5: Solve for x
   x = 681,639,692.71/31,978.87
6. Step 6: Final answer
   x = 21,315.32