Finding the Fourth Proportional to 7,980.84, 11,019.98 and 7,140.04

Step by Step Solution

1. Step 1: Write the proportion equation
   7,980.84 : 11,019.98 = 7,140.04 : x
2. Step 2: Convert to fraction form
   7,980.84/11,019.98 = 7,140.04/x
3. Step 3: Cross multiply
   7,980.84x = 11,019.98 × 7,140.04
4. Step 4: Simplify right side
   7,980.84x = 78,683,098.00
5. Step 5: Solve for x
   x = 78,683,098.00/7,980.84
6. Step 6: Final answer
   x = 9,859.00