Finding the Fourth Proportional to 2,647.89, 3,971.30 and 1,331.28

Step by Step Solution

1. Step 1: Write the proportion equation
   2,647.89 : 3,971.30 = 1,331.28 : x
2. Step 2: Convert to fraction form
   2,647.89/3,971.30 = 1,331.28/x
3. Step 3: Cross multiply
   2,647.89x = 3,971.30 × 1,331.28
4. Step 4: Simplify right side
   2,647.89x = 5,286,905.61
5. Step 5: Solve for x
   x = 5,286,905.61/2,647.89
6. Step 6: Final answer
   x = 1,996.65