Finding the Fourth Proportional to 5,401.89, 8,091.90 and 4,220.91

Step by Step Solution

1. Step 1: Write the proportion equation
   5,401.89 : 8,091.90 = 4,220.91 : x
2. Step 2: Convert to fraction form
   5,401.89/8,091.90 = 4,220.91/x
3. Step 3: Cross multiply
   5,401.89x = 8,091.90 × 4,220.91
4. Step 4: Simplify right side
   5,401.89x = 34,155,181.63
5. Step 5: Solve for x
   x = 34,155,181.63/5,401.89
6. Step 6: Final answer
   x = 6,322.82