Finding the Fourth Proportional to 2,123.18, 2,930.32 and 1,239.50

Step by Step Solution

1. Step 1: Write the proportion equation
   2,123.18 : 2,930.32 = 1,239.50 : x
2. Step 2: Convert to fraction form
   2,123.18/2,930.32 = 1,239.50/x
3. Step 3: Cross multiply
   2,123.18x = 2,930.32 × 1,239.50
4. Step 4: Simplify right side
   2,123.18x = 3,632,131.64
5. Step 5: Solve for x
   x = 3,632,131.64/2,123.18
6. Step 6: Final answer
   x = 1,710.70