Finding the Fourth Proportional to 28,321.42, 42,399.06 and 19,858.58

Step by Step Solution

1. Step 1: Write the proportion equation
   28,321.42 : 42,399.06 = 19,858.58 : x
2. Step 2: Convert to fraction form
   28,321.42/42,399.06 = 19,858.58/x
3. Step 3: Cross multiply
   28,321.42x = 42,399.06 × 19,858.58
4. Step 4: Simplify right side
   28,321.42x = 841,985,124.93
5. Step 5: Solve for x
   x = 841,985,124.93/28,321.42
6. Step 6: Final answer
   x = 29,729.62