Finding the Fourth Proportional to 2,139.78, 3,210.12 and 1,475.52

Step by Step Solution

1. Step 1: Write the proportion equation
   2,139.78 : 3,210.12 = 1,475.52 : x
2. Step 2: Convert to fraction form
   2,139.78/3,210.12 = 1,475.52/x
3. Step 3: Cross multiply
   2,139.78x = 3,210.12 × 1,475.52
4. Step 4: Simplify right side
   2,139.78x = 4,736,596.26
5. Step 5: Solve for x
   x = 4,736,596.26/2,139.78
6. Step 6: Final answer
   x = 2,213.59