Finding the Fourth Proportional to 12,428.75, 17,152.42 and 7,123.91

Step by Step Solution

1. Step 1: Write the proportion equation
   12,428.75 : 17,152.42 = 7,123.91 : x
2. Step 2: Convert to fraction form
   12,428.75/17,152.42 = 7,123.91/x
3. Step 3: Cross multiply
   12,428.75x = 17,152.42 × 7,123.91
4. Step 4: Simplify right side
   12,428.75x = 122,192,296.36
5. Step 5: Solve for x
   x = 122,192,296.36/12,428.75
6. Step 6: Final answer
   x = 9,831.42