Finding the Fourth Proportional to 7,086.99, 9,779.78 and 3,900.10

Step by Step Solution

1. Step 1: Write the proportion equation
   7,086.99 : 9,779.78 = 3,900.10 : x
2. Step 2: Convert to fraction form
   7,086.99/9,779.78 = 3,900.10/x
3. Step 3: Cross multiply
   7,086.99x = 9,779.78 × 3,900.10
4. Step 4: Simplify right side
   7,086.99x = 38,142,119.98
5. Step 5: Solve for x
   x = 38,142,119.98/7,086.99
6. Step 6: Final answer
   x = 5,381.99