Finding the Fourth Proportional to 12,139.92, 18,210.69 and 4,743.90

Step by Step Solution

1. Step 1: Write the proportion equation
   12,139.92 : 18,210.69 = 4,743.90 : x
2. Step 2: Convert to fraction form
   12,139.92/18,210.69 = 4,743.90/x
3. Step 3: Cross multiply
   12,139.92x = 18,210.69 × 4,743.90
4. Step 4: Simplify right side
   12,139.92x = 86,389,692.29
5. Step 5: Solve for x
   x = 86,389,692.29/12,139.92
6. Step 6: Final answer
   x = 7,116.17