Finding the Fourth Proportional to 31,071.16, 42,864.55 and 20,995.92

Step by Step Solution

1. Step 1: Write the proportion equation
   31,071.16 : 42,864.55 = 20,995.92 : x
2. Step 2: Convert to fraction form
   31,071.16/42,864.55 = 20,995.92/x
3. Step 3: Cross multiply
   31,071.16x = 42,864.55 × 20,995.92
4. Step 4: Simplify right side
   31,071.16x = 899,980,662.64
5. Step 5: Solve for x
   x = 899,980,662.64/31,071.16
6. Step 6: Final answer
   x = 28,965.15