Finding the Fourth Proportional to 21,019.26, 31,499.73 and 10,618.86

Step by Step Solution

1. Step 1: Write the proportion equation
   21,019.26 : 31,499.73 = 10,618.86 : x
2. Step 2: Convert to fraction form
   21,019.26/31,499.73 = 10,618.86/x
3. Step 3: Cross multiply
   21,019.26x = 31,499.73 × 10,618.86
4. Step 4: Simplify right side
   21,019.26x = 334,491,222.91
5. Step 5: Solve for x
   x = 334,491,222.91/21,019.26
6. Step 6: Final answer
   x = 15,913.56