Finding the Fourth Proportional to 31,878.60, 47,776.04 and 13,148.31

Step by Step Solution

1. Step 1: Write the proportion equation
   31,878.60 : 47,776.04 = 13,148.31 : x
2. Step 2: Convert to fraction form
   31,878.60/47,776.04 = 13,148.31/x
3. Step 3: Cross multiply
   31,878.60x = 47,776.04 × 13,148.31
4. Step 4: Simplify right side
   31,878.60x = 628,174,298.52
5. Step 5: Solve for x
   x = 628,174,298.52/31,878.60
6. Step 6: Final answer
   x = 19,705.20