Finding the Fourth Proportional to 1,310.82, 1,808.89 and 721.34

Step by Step Solution

1. Step 1: Write the proportion equation
   1,310.82 : 1,808.89 = 721.34 : x
2. Step 2: Convert to fraction form
   1,310.82/1,808.89 = 721.34/x
3. Step 3: Cross multiply
   1,310.82x = 1,808.89 × 721.34
4. Step 4: Simplify right side
   1,310.82x = 1,304,824.71
5. Step 5: Solve for x
   x = 1,304,824.71/1,310.82
6. Step 6: Final answer
   x = 995.43