Finding the Fourth Proportional to 99,611.78, 137,469.12 and 56,018.05

Step by Step Solution

1. Step 1: Write the proportion equation
   99,611.78 : 137,469.12 = 56,018.05 : x
2. Step 2: Convert to fraction form
   99,611.78/137,469.12 = 56,018.05/x
3. Step 3: Cross multiply
   99,611.78x = 137,469.12 × 56,018.05
4. Step 4: Simplify right side
   99,611.78x = 7,700,751,483.88
5. Step 5: Solve for x
   x = 7,700,751,483.88/99,611.78
6. Step 6: Final answer
   x = 77,307.64