Finding the Fourth Proportional to 1,381.50, 1,906.54 and 857.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,381.50 : 1,906.54 = 857.42 : x
2. Step 2: Convert to fraction form
   1,381.50/1,906.54 = 857.42/x
3. Step 3: Cross multiply
   1,381.50x = 1,906.54 × 857.42
4. Step 4: Simplify right side
   1,381.50x = 1,634,705.53
5. Step 5: Solve for x
   x = 1,634,705.53/1,381.50
6. Step 6: Final answer
   x = 1,183.28