Finding the Fourth Proportional to 711.98, 1,069.89 and 671.88

Step by Step Solution

1. Step 1: Write the proportion equation
   711.98 : 1,069.89 = 671.88 : x
2. Step 2: Convert to fraction form
   711.98/1,069.89 = 671.88/x
3. Step 3: Cross multiply
   711.98x = 1,069.89 × 671.88
4. Step 4: Simplify right side
   711.98x = 718,837.69
5. Step 5: Solve for x
   x = 718,837.69/711.98
6. Step 6: Final answer
   x = 1,009.63