Finding the Fourth Proportional to 13,388.16, 18,475.77 and 7,419.90

Step by Step Solution

1. Step 1: Write the proportion equation
   13,388.16 : 18,475.77 = 7,419.90 : x
2. Step 2: Convert to fraction form
   13,388.16/18,475.77 = 7,419.90/x
3. Step 3: Cross multiply
   13,388.16x = 18,475.77 × 7,419.90
4. Step 4: Simplify right side
   13,388.16x = 137,088,365.82
5. Step 5: Solve for x
   x = 137,088,365.82/13,388.16
6. Step 6: Final answer
   x = 10,239.52