Finding the Fourth Proportional to 1,238.47, 1,857.70 and 498.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,238.47 : 1,857.70 = 498.42 : x
2. Step 2: Convert to fraction form
   1,238.47/1,857.70 = 498.42/x
3. Step 3: Cross multiply
   1,238.47x = 1,857.70 × 498.42
4. Step 4: Simplify right side
   1,238.47x = 925,915.46
5. Step 5: Solve for x
   x = 925,915.46/1,238.47
6. Step 6: Final answer
   x = 747.63