Finding the Fourth Proportional to 28,109.94, 42,171.31 and 9,640.82

Step by Step Solution

1. Step 1: Write the proportion equation
   28,109.94 : 42,171.31 = 9,640.82 : x
2. Step 2: Convert to fraction form
   28,109.94/42,171.31 = 9,640.82/x
3. Step 3: Cross multiply
   28,109.94x = 42,171.31 × 9,640.82
4. Step 4: Simplify right side
   28,109.94x = 406,566,008.87
5. Step 5: Solve for x
   x = 406,566,008.87/28,109.94
6. Step 6: Final answer
   x = 14,463.42