Finding the Fourth Proportional to 1,451.61, 2,002.56 and 861.81

Step by Step Solution

1. Step 1: Write the proportion equation
   1,451.61 : 2,002.56 = 861.81 : x
2. Step 2: Convert to fraction form
   1,451.61/2,002.56 = 861.81/x
3. Step 3: Cross multiply
   1,451.61x = 2,002.56 × 861.81
4. Step 4: Simplify right side
   1,451.61x = 1,725,826.23
5. Step 5: Solve for x
   x = 1,725,826.23/1,451.61
6. Step 6: Final answer
   x = 1,188.90