Finding the Fourth Proportional to 2,123.68, 2,930.86 and 1,239.77

Step by Step Solution

1. Step 1: Write the proportion equation
   2,123.68 : 2,930.86 = 1,239.77 : x
2. Step 2: Convert to fraction form
   2,123.68/2,930.86 = 1,239.77/x
3. Step 3: Cross multiply
   2,123.68x = 2,930.86 × 1,239.77
4. Step 4: Simplify right side
   2,123.68x = 3,633,588.07
5. Step 5: Solve for x
   x = 3,633,588.07/2,123.68
6. Step 6: Final answer
   x = 1,710.99