Finding the Fourth Proportional to 1,238.05, 1,708.52 and 678.53

Step by Step Solution

1. Step 1: Write the proportion equation
   1,238.05 : 1,708.52 = 678.53 : x
2. Step 2: Convert to fraction form
   1,238.05/1,708.52 = 678.53/x
3. Step 3: Cross multiply
   1,238.05x = 1,708.52 × 678.53
4. Step 4: Simplify right side
   1,238.05x = 1,159,275.23
5. Step 5: Solve for x
   x = 1,159,275.23/1,238.05
6. Step 6: Final answer
   x = 936.37