Finding the Fourth Proportional to 1,080.71, 1,491.89 and 707.71

Step by Step Solution

1. Step 1: Write the proportion equation
   1,080.71 : 1,491.89 = 707.71 : x
2. Step 2: Convert to fraction form
   1,080.71/1,491.89 = 707.71/x
3. Step 3: Cross multiply
   1,080.71x = 1,491.89 × 707.71
4. Step 4: Simplify right side
   1,080.71x = 1,055,814.47
5. Step 5: Solve for x
   x = 1,055,814.47/1,080.71
6. Step 6: Final answer
   x = 976.96