Finding the Fourth Proportional to 31,115.82, 42,942.40 and 17,691.30

Step by Step Solution

1. Step 1: Write the proportion equation
   31,115.82 : 42,942.40 = 17,691.30 : x
2. Step 2: Convert to fraction form
   31,115.82/42,942.40 = 17,691.30/x
3. Step 3: Cross multiply
   31,115.82x = 42,942.40 × 17,691.30
4. Step 4: Simplify right side
   31,115.82x = 759,706,881.12
5. Step 5: Solve for x
   x = 759,706,881.12/31,115.82
6. Step 6: Final answer
   x = 24,415.45