Finding the Fourth Proportional to 1,238.89, 1,858.20 and 498.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,238.89 : 1,858.20 = 498.82 : x
2. Step 2: Convert to fraction form
   1,238.89/1,858.20 = 498.82/x
3. Step 3: Cross multiply
   1,238.89x = 1,858.20 × 498.82
4. Step 4: Simplify right side
   1,238.89x = 926,907.32
5. Step 5: Solve for x
   x = 926,907.32/1,238.89
6. Step 6: Final answer
   x = 748.18