Finding the Fourth Proportional to 56,639.50, 78,162.60 and 31,489

Step by Step Solution

1. Step 1: Write the proportion equation
   56,639.50 : 78,162.60 = 31,489 : x
2. Step 2: Convert to fraction form
   56,639.50/78,162.60 = 31,489/x
3. Step 3: Cross multiply
   56,639.50x = 78,162.60 × 31,489
4. Step 4: Simplify right side
   56,639.50x = 2,461,262,111.40
5. Step 5: Solve for x
   x = 2,461,262,111.40/56,639.50
6. Step 6: Final answer
   x = 43,454.87