Finding the Fourth Proportional to 13,087.83, 18,061.21 and 7,420.76

Step by Step Solution

1. Step 1: Write the proportion equation
   13,087.83 : 18,061.21 = 7,420.76 : x
2. Step 2: Convert to fraction form
   13,087.83/18,061.21 = 7,420.76/x
3. Step 3: Cross multiply
   13,087.83x = 18,061.21 × 7,420.76
4. Step 4: Simplify right side
   13,087.83x = 134,027,993.01
5. Step 5: Solve for x
   x = 134,027,993.01/13,087.83
6. Step 6: Final answer
   x = 10,240.66