Finding the Fourth Proportional to 1,359.21, 1,875.38 and 861.67

Step by Step Solution

1. Step 1: Write the proportion equation
   1,359.21 : 1,875.38 = 861.67 : x
2. Step 2: Convert to fraction form
   1,359.21/1,875.38 = 861.67/x
3. Step 3: Cross multiply
   1,359.21x = 1,875.38 × 861.67
4. Step 4: Simplify right side
   1,359.21x = 1,615,954.38
5. Step 5: Solve for x
   x = 1,615,954.38/1,359.21
6. Step 6: Final answer
   x = 1,188.89