Finding the Fourth Proportional to 1,356.50, 1,870.98 and 858.66

Step by Step Solution

1. Step 1: Write the proportion equation
   1,356.50 : 1,870.98 = 858.66 : x
2. Step 2: Convert to fraction form
   1,356.50/1,870.98 = 858.66/x
3. Step 3: Cross multiply
   1,356.50x = 1,870.98 × 858.66
4. Step 4: Simplify right side
   1,356.50x = 1,606,535.69
5. Step 5: Solve for x
   x = 1,606,535.69/1,356.50
6. Step 6: Final answer
   x = 1,184.32