Finding the Fourth Proportional to 8,870.16, 12,240.87 and 4,891.20

Step by Step Solution

1. Step 1: Write the proportion equation
   8,870.16 : 12,240.87 = 4,891.20 : x
2. Step 2: Convert to fraction form
   8,870.16/12,240.87 = 4,891.20/x
3. Step 3: Cross multiply
   8,870.16x = 12,240.87 × 4,891.20
4. Step 4: Simplify right side
   8,870.16x = 59,872,543.34
5. Step 5: Solve for x
   x = 59,872,543.34/8,870.16
6. Step 6: Final answer
   x = 6,749.88