Finding the Fourth Proportional to 20,900.06, 31,349.68 and 5,105.19

Step by Step Solution

1. Step 1: Write the proportion equation
   20,900.06 : 31,349.68 = 5,105.19 : x
2. Step 2: Convert to fraction form
   20,900.06/31,349.68 = 5,105.19/x
3. Step 3: Cross multiply
   20,900.06x = 31,349.68 × 5,105.19
4. Step 4: Simplify right side
   20,900.06x = 160,046,047.31
5. Step 5: Solve for x
   x = 160,046,047.31/20,900.06
6. Step 6: Final answer
   x = 7,657.69