Finding the Fourth Proportional to 1,354.86, 1,870.85 and 858.38

Step by Step Solution

1. Step 1: Write the proportion equation
   1,354.86 : 1,870.85 = 858.38 : x
2. Step 2: Convert to fraction form
   1,354.86/1,870.85 = 858.38/x
3. Step 3: Cross multiply
   1,354.86x = 1,870.85 × 858.38
4. Step 4: Simplify right side
   1,354.86x = 1,605,900.22
5. Step 5: Solve for x
   x = 1,605,900.22/1,354.86
6. Step 6: Final answer
   x = 1,185.29