Finding the Fourth Proportional to 12,139.63, 18,210.81 and 3,820.84

Step by Step Solution

1. Step 1: Write the proportion equation
   12,139.63 : 18,210.81 = 3,820.84 : x
2. Step 2: Convert to fraction form
   12,139.63/18,210.81 = 3,820.84/x
3. Step 3: Cross multiply
   12,139.63x = 18,210.81 × 3,820.84
4. Step 4: Simplify right side
   12,139.63x = 69,580,591.28
5. Step 5: Solve for x
   x = 69,580,591.28/12,139.63
6. Step 6: Final answer
   x = 5,731.69