Finding the Fourth Proportional to 99,820.10, 149,730.15 and 89,978.60

Step by Step Solution

1. Step 1: Write the proportion equation
   99,820.10 : 149,730.15 = 89,978.60 : x
2. Step 2: Convert to fraction form
   99,820.10/149,730.15 = 89,978.60/x
3. Step 3: Cross multiply
   99,820.10x = 149,730.15 × 89,978.60
4. Step 4: Simplify right side
   99,820.10x = 13,472,509,274.79
5. Step 5: Solve for x
   x = 13,472,509,274.79/99,820.10
6. Step 6: Final answer
   x = 134,967.90