Finding the Fourth Proportional to 7,172.84, 9,898.18 and 3,986.34

Step by Step Solution

1. Step 1: Write the proportion equation
   7,172.84 : 9,898.18 = 3,986.34 : x
2. Step 2: Convert to fraction form
   7,172.84/9,898.18 = 3,986.34/x
3. Step 3: Cross multiply
   7,172.84x = 9,898.18 × 3,986.34
4. Step 4: Simplify right side
   7,172.84x = 39,457,510.86
5. Step 5: Solve for x
   x = 39,457,510.86/7,172.84
6. Step 6: Final answer
   x = 5,500.96