Finding the Fourth Proportional to 1,139.00, 1,707.65 and 445.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,139.00 : 1,707.65 = 445.31 : x
2. Step 2: Convert to fraction form
   1,139.00/1,707.65 = 445.31/x
3. Step 3: Cross multiply
   1,139.00x = 1,707.65 × 445.31
4. Step 4: Simplify right side
   1,139.00x = 760,431.39
5. Step 5: Solve for x
   x = 760,431.39/1,139.00
6. Step 6: Final answer
   x = 667.63