Finding the Fourth Proportional to 1,238.94, 1,709.82 and 715.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,238.94 : 1,709.82 = 715.05 : x
2. Step 2: Convert to fraction form
   1,238.94/1,709.82 = 715.05/x
3. Step 3: Cross multiply
   1,238.94x = 1,709.82 × 715.05
4. Step 4: Simplify right side
   1,238.94x = 1,222,606.79
5. Step 5: Solve for x
   x = 1,222,606.79/1,238.94
6. Step 6: Final answer
   x = 986.82