Finding the Fourth Proportional to 156,978.50, 216,649.95 and 89,910.50

Step by Step Solution

1. Step 1: Write the proportion equation
   156,978.50 : 216,649.95 = 89,910.50 : x
2. Step 2: Convert to fraction form
   156,978.50/216,649.95 = 89,910.50/x
3. Step 3: Cross multiply
   156,978.50x = 216,649.95 × 89,910.50
4. Step 4: Simplify right side
   156,978.50x = 19,479,105,329.48
5. Step 5: Solve for x
   x = 19,479,105,329.48/156,978.50
6. Step 6: Final answer
   x = 124,087.73