Finding the Fourth Proportional to 13,388.54, 18,476.32 and 7,420.28

Step by Step Solution

1. Step 1: Write the proportion equation
   13,388.54 : 18,476.32 = 7,420.28 : x
2. Step 2: Convert to fraction form
   13,388.54/18,476.32 = 7,420.28/x
3. Step 3: Cross multiply
   13,388.54x = 18,476.32 × 7,420.28
4. Step 4: Simplify right side
   13,388.54x = 137,099,467.77
5. Step 5: Solve for x
   x = 137,099,467.77/13,388.54
6. Step 6: Final answer
   x = 10,240.06