Finding the Fourth Proportional to 9,155.06, 12,642.94 and 7,820.98

Step by Step Solution

1. Step 1: Write the proportion equation
   9,155.06 : 12,642.94 = 7,820.98 : x
2. Step 2: Convert to fraction form
   9,155.06/12,642.94 = 7,820.98/x
3. Step 3: Cross multiply
   9,155.06x = 12,642.94 × 7,820.98
4. Step 4: Simplify right side
   9,155.06x = 98,880,180.88
5. Step 5: Solve for x
   x = 98,880,180.88/9,155.06
6. Step 6: Final answer
   x = 10,800.60