Finding the Fourth Proportional to 1,296.78, 1,789.53 and 707.31

Step by Step Solution

1. Step 1: Write the proportion equation
   1,296.78 : 1,789.53 = 707.31 : x
2. Step 2: Convert to fraction form
   1,296.78/1,789.53 = 707.31/x
3. Step 3: Cross multiply
   1,296.78x = 1,789.53 × 707.31
4. Step 4: Simplify right side
   1,296.78x = 1,265,752.46
5. Step 5: Solve for x
   x = 1,265,752.46/1,296.78
6. Step 6: Final answer
   x = 976.07