Finding the Fourth Proportional to 31,070.38, 42,863.48 and 20,995.15

Step by Step Solution

1. Step 1: Write the proportion equation
   31,070.38 : 42,863.48 = 20,995.15 : x
2. Step 2: Convert to fraction form
   31,070.38/42,863.48 = 20,995.15/x
3. Step 3: Cross multiply
   31,070.38x = 42,863.48 × 20,995.15
4. Step 4: Simplify right side
   31,070.38x = 899,924,977.80
5. Step 5: Solve for x
   x = 899,924,977.80/31,070.38
6. Step 6: Final answer
   x = 28,964.08