Finding the Fourth Proportional to 1,397.86, 2,093.91 and 820.42

Step by Step Solution

1. Step 1: Write the proportion equation
   1,397.86 : 2,093.91 = 820.42 : x
2. Step 2: Convert to fraction form
   1,397.86/2,093.91 = 820.42/x
3. Step 3: Cross multiply
   1,397.86x = 2,093.91 × 820.42
4. Step 4: Simplify right side
   1,397.86x = 1,717,885.64
5. Step 5: Solve for x
   x = 1,717,885.64/1,397.86
6. Step 6: Final answer
   x = 1,228.94