Finding the Fourth Proportional to 1,383.59, 1,910.63 and 879.60

Step by Step Solution

1. Step 1: Write the proportion equation
   1,383.59 : 1,910.63 = 879.60 : x
2. Step 2: Convert to fraction form
   1,383.59/1,910.63 = 879.60/x
3. Step 3: Cross multiply
   1,383.59x = 1,910.63 × 879.60
4. Step 4: Simplify right side
   1,383.59x = 1,680,585.75
5. Step 5: Solve for x
   x = 1,680,585.75/1,383.59
6. Step 6: Final answer
   x = 1,214.66