Finding the Fourth Proportional to 1,007.49, 1,390.37 and 588.11

Step by Step Solution

1. Step 1: Write the proportion equation
   1,007.49 : 1,390.37 = 588.11 : x
2. Step 2: Convert to fraction form
   1,007.49/1,390.37 = 588.11/x
3. Step 3: Cross multiply
   1,007.49x = 1,390.37 × 588.11
4. Step 4: Simplify right side
   1,007.49x = 817,680.61
5. Step 5: Solve for x
   x = 817,680.61/1,007.49
6. Step 6: Final answer
   x = 811.61