Finding the Fourth Proportional to 1,356.49, 1,871.31 and 859.87

Step by Step Solution

1. Step 1: Write the proportion equation
   1,356.49 : 1,871.31 = 859.87 : x
2. Step 2: Convert to fraction form
   1,356.49/1,871.31 = 859.87/x
3. Step 3: Cross multiply
   1,356.49x = 1,871.31 × 859.87
4. Step 4: Simplify right side
   1,356.49x = 1,609,083.33
5. Step 5: Solve for x
   x = 1,609,083.33/1,356.49
6. Step 6: Final answer
   x = 1,186.21