Finding the Fourth Proportional to 1,308.78, 1,806.15 and 719.33

Step by Step Solution

1. Step 1: Write the proportion equation
   1,308.78 : 1,806.15 = 719.33 : x
2. Step 2: Convert to fraction form
   1,308.78/1,806.15 = 719.33/x
3. Step 3: Cross multiply
   1,308.78x = 1,806.15 × 719.33
4. Step 4: Simplify right side
   1,308.78x = 1,299,213.36
5. Step 5: Solve for x
   x = 1,299,213.36/1,308.78
6. Step 6: Final answer
   x = 992.69