Finding the Fourth Proportional to 28,456.12, 42,673.25 and 19,664.38

Step by Step Solution

1. Step 1: Write the proportion equation
   28,456.12 : 42,673.25 = 19,664.38 : x
2. Step 2: Convert to fraction form
   28,456.12/42,673.25 = 19,664.38/x
3. Step 3: Cross multiply
   28,456.12x = 42,673.25 × 19,664.38
4. Step 4: Simplify right side
   28,456.12x = 839,142,905.51
5. Step 5: Solve for x
   x = 839,142,905.51/28,456.12
6. Step 6: Final answer
   x = 29,489.01