Finding the Fourth Proportional to 1,786.30, 2,680.56 and 861.96

Step by Step Solution

1. Step 1: Write the proportion equation
   1,786.30 : 2,680.56 = 861.96 : x
2. Step 2: Convert to fraction form
   1,786.30/2,680.56 = 861.96/x
3. Step 3: Cross multiply
   1,786.30x = 2,680.56 × 861.96
4. Step 4: Simplify right side
   1,786.30x = 2,310,535.50
5. Step 5: Solve for x
   x = 2,310,535.50/1,786.30
6. Step 6: Final answer
   x = 1,293.48