Finding the Fourth Proportional to 2,104.24, 3,156.42 and 870.80

Step by Step Solution

1. Step 1: Write the proportion equation
   2,104.24 : 3,156.42 = 870.80 : x
2. Step 2: Convert to fraction form
   2,104.24/3,156.42 = 870.80/x
3. Step 3: Cross multiply
   2,104.24x = 3,156.42 × 870.80
4. Step 4: Simplify right side
   2,104.24x = 2,748,610.54
5. Step 5: Solve for x
   x = 2,748,610.54/2,104.24
6. Step 6: Final answer
   x = 1,306.22