Finding the Fourth Proportional to 2,123.82, 2,930.99 and 1,239.57

Step by Step Solution

1. Step 1: Write the proportion equation
   2,123.82 : 2,930.99 = 1,239.57 : x
2. Step 2: Convert to fraction form
   2,123.82/2,930.99 = 1,239.57/x
3. Step 3: Cross multiply
   2,123.82x = 2,930.99 × 1,239.57
4. Step 4: Simplify right side
   2,123.82x = 3,633,161.08
5. Step 5: Solve for x
   x = 3,633,161.08/2,123.82
6. Step 6: Final answer
   x = 1,710.67