Finding the Fourth Proportional to 21,019.86, 31,365.81 and 19,156.86

Step by Step Solution

1. Step 1: Write the proportion equation
   21,019.86 : 31,365.81 = 19,156.86 : x
2. Step 2: Convert to fraction form
   21,019.86/31,365.81 = 19,156.86/x
3. Step 3: Cross multiply
   21,019.86x = 31,365.81 × 19,156.86
4. Step 4: Simplify right side
   21,019.86x = 600,870,430.96
5. Step 5: Solve for x
   x = 600,870,430.96/21,019.86
6. Step 6: Final answer
   x = 28,585.84