Finding the Fourth Proportional to 1,915.27, 2,874.27 and 820.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,915.27 : 2,874.27 = 820.42 : x
2. Step 2: Convert to fraction form
   1,915.27/2,874.27 = 820.42/x
3. Step 3: Cross multiply
   1,915.27x = 2,874.27 × 820.42
4. Step 4: Simplify right side
   1,915.27x = 2,358,108.59
5. Step 5: Solve for x
   x = 2,358,108.59/1,915.27
6. Step 6: Final answer
   x = 1,231.21