Finding the Fourth Proportional to 1,238.82, 1,709.58 and 679.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,238.82 : 1,709.58 = 679.30 : x
2. Step 2: Convert to fraction form
   1,238.82/1,709.58 = 679.30/x
3. Step 3: Cross multiply
   1,238.82x = 1,709.58 × 679.30
4. Step 4: Simplify right side
   1,238.82x = 1,161,317.69
5. Step 5: Solve for x
   x = 1,161,317.69/1,238.82
6. Step 6: Final answer
   x = 937.44