Finding the Fourth Proportional to 1,356.72, 1,872.39 and 859.51

Step by Step Solution

1. Step 1: Write the proportion equation
   1,356.72 : 1,872.39 = 859.51 : x
2. Step 2: Convert to fraction form
   1,356.72/1,872.39 = 859.51/x
3. Step 3: Cross multiply
   1,356.72x = 1,872.39 × 859.51
4. Step 4: Simplify right side
   1,356.72x = 1,609,337.93
5. Step 5: Solve for x
   x = 1,609,337.93/1,356.72
6. Step 6: Final answer
   x = 1,186.20