Finding the Fourth Proportional to 1,921.70, 2,880.82 and 688.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,921.70 : 2,880.82 = 688.82 : x
2. Step 2: Convert to fraction form
   1,921.70/2,880.82 = 688.82/x
3. Step 3: Cross multiply
   1,921.70x = 2,880.82 × 688.82
4. Step 4: Simplify right side
   1,921.70x = 1,984,363.27
5. Step 5: Solve for x
   x = 1,984,363.27/1,921.70
6. Step 6: Final answer
   x = 1,032.61