Finding the Fourth Proportional to 1,569.34, 2,165.85 and 870.72

Step by Step Solution

1. Step 1: Write the proportion equation
   1,569.34 : 2,165.85 = 870.72 : x
2. Step 2: Convert to fraction form
   1,569.34/2,165.85 = 870.72/x
3. Step 3: Cross multiply
   1,569.34x = 2,165.85 × 870.72
4. Step 4: Simplify right side
   1,569.34x = 1,885,848.91
5. Step 5: Solve for x
   x = 1,885,848.91/1,569.34
6. Step 6: Final answer
   x = 1,201.68