Finding the Fourth Proportional to 1,913.24, 2,870.17 and 680.39

Step by Step Solution

1. Step 1: Write the proportion equation
   1,913.24 : 2,870.17 = 680.39 : x
2. Step 2: Convert to fraction form
   1,913.24/2,870.17 = 680.39/x
3. Step 3: Cross multiply
   1,913.24x = 2,870.17 × 680.39
4. Step 4: Simplify right side
   1,913.24x = 1,952,820.62
5. Step 5: Solve for x
   x = 1,952,820.62/1,913.24
6. Step 6: Final answer
   x = 1,020.69