Finding the Fourth Proportional to 10,815.67, 16,225.80 and 3,420.72

Step by Step Solution

1. Step 1: Write the proportion equation
   10,815.67 : 16,225.80 = 3,420.72 : x
2. Step 2: Convert to fraction form
   10,815.67/16,225.80 = 3,420.72/x
3. Step 3: Cross multiply
   10,815.67x = 16,225.80 × 3,420.72
4. Step 4: Simplify right side
   10,815.67x = 55,503,918.58
5. Step 5: Solve for x
   x = 55,503,918.58/10,815.67
6. Step 6: Final answer
   x = 5,131.81