Finding the Fourth Proportional to 105,630.38, 158,338.89 and 66,215.12

Step by Step Solution

1. Step 1: Write the proportion equation
   105,630.38 : 158,338.89 = 66,215.12 : x
2. Step 2: Convert to fraction form
   105,630.38/158,338.89 = 66,215.12/x
3. Step 3: Cross multiply
   105,630.38x = 158,338.89 × 66,215.12
4. Step 4: Simplify right side
   105,630.38x = 10,484,428,602.02
5. Step 5: Solve for x
   x = 10,484,428,602.02/105,630.38
6. Step 6: Final answer
   x = 99,255.81