Finding the Fourth Proportional to 2,128.06, 3,191.82 and 830.44

Step by Step Solution

1. Step 1: Write the proportion equation
   2,128.06 : 3,191.82 = 830.44 : x
2. Step 2: Convert to fraction form
   2,128.06/3,191.82 = 830.44/x
3. Step 3: Cross multiply
   2,128.06x = 3,191.82 × 830.44
4. Step 4: Simplify right side
   2,128.06x = 2,650,615.00
5. Step 5: Solve for x
   x = 2,650,615.00/2,128.06
6. Step 6: Final answer
   x = 1,245.55