Finding the Fourth Proportional to 1,173.28, 1,620.54 and 879.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,173.28 : 1,620.54 = 879.82 : x
2. Step 2: Convert to fraction form
   1,173.28/1,620.54 = 879.82/x
3. Step 3: Cross multiply
   1,173.28x = 1,620.54 × 879.82
4. Step 4: Simplify right side
   1,173.28x = 1,425,783.50
5. Step 5: Solve for x
   x = 1,425,783.50/1,173.28
6. Step 6: Final answer
   x = 1,215.21