Finding the Fourth Proportional to 105,663.26, 145,830.25 and 65,390

Step by Step Solution

1. Step 1: Write the proportion equation
   105,663.26 : 145,830.25 = 65,390 : x
2. Step 2: Convert to fraction form
   105,663.26/145,830.25 = 65,390/x
3. Step 3: Cross multiply
   105,663.26x = 145,830.25 × 65,390
4. Step 4: Simplify right side
   105,663.26x = 9,535,840,047.50
5. Step 5: Solve for x
   x = 9,535,840,047.50/105,663.26
6. Step 6: Final answer
   x = 90,247.45