Finding the Fourth Proportional to 1,109.83, 1,664.90 and 879.15

Step by Step Solution

1. Step 1: Write the proportion equation
   1,109.83 : 1,664.90 = 879.15 : x
2. Step 2: Convert to fraction form
   1,109.83/1,664.90 = 879.15/x
3. Step 3: Cross multiply
   1,109.83x = 1,664.90 × 879.15
4. Step 4: Simplify right side
   1,109.83x = 1,463,696.84
5. Step 5: Solve for x
   x = 1,463,696.84/1,109.83
6. Step 6: Final answer
   x = 1,318.85