Finding the Fourth Proportional to 1,247.59, 1,867.89 and 661.27

Step by Step Solution

1. Step 1: Write the proportion equation
   1,247.59 : 1,867.89 = 661.27 : x
2. Step 2: Convert to fraction form
   1,247.59/1,867.89 = 661.27/x
3. Step 3: Cross multiply
   1,247.59x = 1,867.89 × 661.27
4. Step 4: Simplify right side
   1,247.59x = 1,235,179.62
5. Step 5: Solve for x
   x = 1,235,179.62/1,247.59
6. Step 6: Final answer
   x = 990.05