Finding the Fourth Proportional to 1,418.90, 1,958.46 and 859.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,418.90 : 1,958.46 = 859.40 : x
2. Step 2: Convert to fraction form
   1,418.90/1,958.46 = 859.40/x
3. Step 3: Cross multiply
   1,418.90x = 1,958.46 × 859.40
4. Step 4: Simplify right side
   1,418.90x = 1,683,100.52
5. Step 5: Solve for x
   x = 1,683,100.52/1,418.90
6. Step 6: Final answer
   x = 1,186.20