Finding the Fourth Proportional to 1,569.20, 2,165.52 and 870.52

Step by Step Solution

1. Step 1: Write the proportion equation
   1,569.20 : 2,165.52 = 870.52 : x
2. Step 2: Convert to fraction form
   1,569.20/2,165.52 = 870.52/x
3. Step 3: Cross multiply
   1,569.20x = 2,165.52 × 870.52
4. Step 4: Simplify right side
   1,569.20x = 1,885,128.47
5. Step 5: Solve for x
   x = 1,885,128.47/1,569.20
6. Step 6: Final answer
   x = 1,201.33