Finding the Fourth Proportional to 105,915.71, 158,909.97 and 66,426.59

Step by Step Solution

1. Step 1: Write the proportion equation
   105,915.71 : 158,909.97 = 66,426.59 : x
2. Step 2: Convert to fraction form
   105,915.71/158,909.97 = 66,426.59/x
3. Step 3: Cross multiply
   105,915.71x = 158,909.97 × 66,426.59
4. Step 4: Simplify right side
   105,915.71x = 10,555,847,424.10
5. Step 5: Solve for x
   x = 10,555,847,424.10/105,915.71
6. Step 6: Final answer
   x = 99,662.72