Finding the Fourth Proportional to 2,078.50, 2,868.70 and 1,239.69

Step by Step Solution

1. Step 1: Write the proportion equation
   2,078.50 : 2,868.70 = 1,239.69 : x
2. Step 2: Convert to fraction form
   2,078.50/2,868.70 = 1,239.69/x
3. Step 3: Cross multiply
   2,078.50x = 2,868.70 × 1,239.69
4. Step 4: Simplify right side
   2,078.50x = 3,556,298.70
5. Step 5: Solve for x
   x = 3,556,298.70/2,078.50
6. Step 6: Final answer
   x = 1,710.99