Finding the Fourth Proportional to 212,141.51, 318,002.06 and 99,620.30

Step by Step Solution

1. Step 1: Write the proportion equation
   212,141.51 : 318,002.06 = 99,620.30 : x
2. Step 2: Convert to fraction form
   212,141.51/318,002.06 = 99,620.30/x
3. Step 3: Cross multiply
   212,141.51x = 318,002.06 × 99,620.30
4. Step 4: Simplify right side
   212,141.51x = 31,679,458,529.71
5. Step 5: Solve for x
   x = 31,679,458,529.71/212,141.51
6. Step 6: Final answer
   x = 149,331.73