Finding the Fourth Proportional to 1,569.55, 2,165.89 and 870.88

Step by Step Solution

1. Step 1: Write the proportion equation
   1,569.55 : 2,165.89 = 870.88 : x
2. Step 2: Convert to fraction form
   1,569.55/2,165.89 = 870.88/x
3. Step 3: Cross multiply
   1,569.55x = 2,165.89 × 870.88
4. Step 4: Simplify right side
   1,569.55x = 1,886,215.10
5. Step 5: Solve for x
   x = 1,886,215.10/1,569.55
6. Step 6: Final answer
   x = 1,201.76