Finding the Fourth Proportional to 21,970.89, 30,318.01 and 12,895.28

Step by Step Solution

1. Step 1: Write the proportion equation
   21,970.89 : 30,318.01 = 12,895.28 : x
2. Step 2: Convert to fraction form
   21,970.89/30,318.01 = 12,895.28/x
3. Step 3: Cross multiply
   21,970.89x = 30,318.01 × 12,895.28
4. Step 4: Simplify right side
   21,970.89x = 390,959,090.72
5. Step 5: Solve for x
   x = 390,959,090.72/21,970.89
6. Step 6: Final answer
   x = 17,794.41