Finding the Fourth Proportional to 1,308.05, 1,805.12 and 718.59

Step by Step Solution

1. Step 1: Write the proportion equation
   1,308.05 : 1,805.12 = 718.59 : x
2. Step 2: Convert to fraction form
   1,308.05/1,805.12 = 718.59/x
3. Step 3: Cross multiply
   1,308.05x = 1,805.12 × 718.59
4. Step 4: Simplify right side
   1,308.05x = 1,297,137.59
5. Step 5: Solve for x
   x = 1,297,137.59/1,308.05
6. Step 6: Final answer
   x = 991.66