Finding the Fourth Proportional to 105,068.48, 145,016.08 and 64,239.57

Step by Step Solution

1. Step 1: Write the proportion equation
   105,068.48 : 145,016.08 = 64,239.57 : x
2. Step 2: Convert to fraction form
   105,068.48/145,016.08 = 64,239.57/x
3. Step 3: Cross multiply
   105,068.48x = 145,016.08 × 64,239.57
4. Step 4: Simplify right side
   105,068.48x = 9,315,770,461.69
5. Step 5: Solve for x
   x = 9,315,770,461.69/105,068.48
6. Step 6: Final answer
   x = 88,663.80