Finding the Fourth Proportional to 1,913.76, 2,870.33 and 680.99

Step by Step Solution

1. Step 1: Write the proportion equation
   1,913.76 : 2,870.33 = 680.99 : x
2. Step 2: Convert to fraction form
   1,913.76/2,870.33 = 680.99/x
3. Step 3: Cross multiply
   1,913.76x = 2,870.33 × 680.99
4. Step 4: Simplify right side
   1,913.76x = 1,954,648.27
5. Step 5: Solve for x
   x = 1,954,648.27/1,913.76
6. Step 6: Final answer
   x = 1,021.37