Finding the Fourth Proportional to 10,890.77, 16,337.78 and 3,870.20

Step by Step Solution

1. Step 1: Write the proportion equation
   10,890.77 : 16,337.78 = 3,870.20 : x
2. Step 2: Convert to fraction form
   10,890.77/16,337.78 = 3,870.20/x
3. Step 3: Cross multiply
   10,890.77x = 16,337.78 × 3,870.20
4. Step 4: Simplify right side
   10,890.77x = 63,230,456.81
5. Step 5: Solve for x
   x = 63,230,456.81/10,890.77
6. Step 6: Final answer
   x = 5,805.88