Finding the Fourth Proportional to 1,409.62, 2,116.05 and 865.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,409.62 : 2,116.05 = 865.30 : x
2. Step 2: Convert to fraction form
   1,409.62/2,116.05 = 865.30/x
3. Step 3: Cross multiply
   1,409.62x = 2,116.05 × 865.30
4. Step 4: Simplify right side
   1,409.62x = 1,831,018.07
5. Step 5: Solve for x
   x = 1,831,018.07/1,409.62
6. Step 6: Final answer
   x = 1,298.94