Finding the Fourth Proportional to 1,040.88, 1,434.72 and 709.20

Step by Step Solution

1. Step 1: Write the proportion equation
   1,040.88 : 1,434.72 = 709.20 : x
2. Step 2: Convert to fraction form
   1,040.88/1,434.72 = 709.20/x
3. Step 3: Cross multiply
   1,040.88x = 1,434.72 × 709.20
4. Step 4: Simplify right side
   1,040.88x = 1,017,503.42
5. Step 5: Solve for x
   x = 1,017,503.42/1,040.88
6. Step 6: Final answer
   x = 977.54