Finding the Fourth Proportional to 1,002.34, 1,379.97 and 871.30

Step by Step Solution

1. Step 1: Write the proportion equation
   1,002.34 : 1,379.97 = 871.30 : x
2. Step 2: Convert to fraction form
   1,002.34/1,379.97 = 871.30/x
3. Step 3: Cross multiply
   1,002.34x = 1,379.97 × 871.30
4. Step 4: Simplify right side
   1,002.34x = 1,202,367.86
5. Step 5: Solve for x
   x = 1,202,367.86/1,002.34
6. Step 6: Final answer
   x = 1,199.56