Finding the Fourth Proportional to 10,930.16, 16,390.72 and 3,431.21

Step by Step Solution

1. Step 1: Write the proportion equation
   10,930.16 : 16,390.72 = 3,431.21 : x
2. Step 2: Convert to fraction form
   10,930.16/16,390.72 = 3,431.21/x
3. Step 3: Cross multiply
   10,930.16x = 16,390.72 × 3,431.21
4. Step 4: Simplify right side
   10,930.16x = 56,239,985.22
5. Step 5: Solve for x
   x = 56,239,985.22/10,930.16
6. Step 6: Final answer
   x = 5,145.39