Finding the Fourth Proportional to 20,764.10, 31,145.99 and 5,181.72

Step by Step Solution

1. Step 1: Write the proportion equation
   20,764.10 : 31,145.99 = 5,181.72 : x
2. Step 2: Convert to fraction form
   20,764.10/31,145.99 = 5,181.72/x
3. Step 3: Cross multiply
   20,764.10x = 31,145.99 × 5,181.72
4. Step 4: Simplify right side
   20,764.10x = 161,389,773.39
5. Step 5: Solve for x
   x = 161,389,773.39/20,764.10
6. Step 6: Final answer
   x = 7,772.54