Finding the Fourth Proportional to 21,148.56, 31,715.55 and 7,106.40

Step by Step Solution

1. Step 1: Write the proportion equation
   21,148.56 : 31,715.55 = 7,106.40 : x
2. Step 2: Convert to fraction form
   21,148.56/31,715.55 = 7,106.40/x
3. Step 3: Cross multiply
   21,148.56x = 31,715.55 × 7,106.40
4. Step 4: Simplify right side
   21,148.56x = 225,383,384.52
5. Step 5: Solve for x
   x = 225,383,384.52/21,148.56
6. Step 6: Final answer
   x = 10,657.15