Finding the Fourth Proportional to 31,456.91, 43,419.78 and 18,719.12

Step by Step Solution

1. Step 1: Write the proportion equation
   31,456.91 : 43,419.78 = 18,719.12 : x
2. Step 2: Convert to fraction form
   31,456.91/43,419.78 = 18,719.12/x
3. Step 3: Cross multiply
   31,456.91x = 43,419.78 × 18,719.12
4. Step 4: Simplify right side
   31,456.91x = 812,779,855.09
5. Step 5: Solve for x
   x = 812,779,855.09/31,456.91
6. Step 6: Final answer
   x = 25,837.88