Finding the Fourth Proportional to 9,042.07, 12,478.71 and 5,457.90

Step by Step Solution

1. Step 1: Write the proportion equation
   9,042.07 : 12,478.71 = 5,457.90 : x
2. Step 2: Convert to fraction form
   9,042.07/12,478.71 = 5,457.90/x
3. Step 3: Cross multiply
   9,042.07x = 12,478.71 × 5,457.90
4. Step 4: Simplify right side
   9,042.07x = 68,107,573.60
5. Step 5: Solve for x
   x = 68,107,573.60/9,042.07
6. Step 6: Final answer
   x = 7,532.30