Finding the Fourth Proportional to 13,406.42, 18,501.35 and 8,100.21

Step by Step Solution

1. Step 1: Write the proportion equation
   13,406.42 : 18,501.35 = 8,100.21 : x
2. Step 2: Convert to fraction form
   13,406.42/18,501.35 = 8,100.21/x
3. Step 3: Cross multiply
   13,406.42x = 18,501.35 × 8,100.21
4. Step 4: Simplify right side
   13,406.42x = 149,864,820.28
5. Step 5: Solve for x
   x = 149,864,820.28/13,406.42
6. Step 6: Final answer
   x = 11,178.59