Finding the Fourth Proportional to 2,238.60, 3,358.38 and 678.72

Step by Step Solution

1. Step 1: Write the proportion equation
   2,238.60 : 3,358.38 = 678.72 : x
2. Step 2: Convert to fraction form
   2,238.60/3,358.38 = 678.72/x
3. Step 3: Cross multiply
   2,238.60x = 3,358.38 × 678.72
4. Step 4: Simplify right side
   2,238.60x = 2,279,412.21
5. Step 5: Solve for x
   x = 2,279,412.21/2,238.60
6. Step 6: Final answer
   x = 1,018.23