Finding the Fourth Proportional to 21,061.70, 31,574.19 and 7,910.54

Step by Step Solution

1. Step 1: Write the proportion equation
   21,061.70 : 31,574.19 = 7,910.54 : x
2. Step 2: Convert to fraction form
   21,061.70/31,574.19 = 7,910.54/x
3. Step 3: Cross multiply
   21,061.70x = 31,574.19 × 7,910.54
4. Step 4: Simplify right side
   21,061.70x = 249,768,892.96
5. Step 5: Solve for x
   x = 249,768,892.96/21,061.70
6. Step 6: Final answer
   x = 11,858.91