Finding the Fourth Proportional to 1,359.64, 1,875.59 and 861.43

Step by Step Solution

1. Step 1: Write the proportion equation
   1,359.64 : 1,875.59 = 861.43 : x
2. Step 2: Convert to fraction form
   1,359.64/1,875.59 = 861.43/x
3. Step 3: Cross multiply
   1,359.64x = 1,875.59 × 861.43
4. Step 4: Simplify right side
   1,359.64x = 1,615,675.81
5. Step 5: Solve for x
   x = 1,615,675.81/1,359.64
6. Step 6: Final answer
   x = 1,188.31