Finding the Fourth Proportional to 9,139.47, 13,628.96 and 9,056.31

Step by Step Solution

1. Step 1: Write the proportion equation
   9,139.47 : 13,628.96 = 9,056.31 : x
2. Step 2: Convert to fraction form
   9,139.47/13,628.96 = 9,056.31/x
3. Step 3: Cross multiply
   9,139.47x = 13,628.96 × 9,056.31
4. Step 4: Simplify right side
   9,139.47x = 123,428,041.46
5. Step 5: Solve for x
   x = 123,428,041.46/9,139.47
6. Step 6: Final answer
   x = 13,504.95