Finding the Fourth Proportional to 31,142.67, 42,963.80 and 21,716.70

Step by Step Solution

1. Step 1: Write the proportion equation
   31,142.67 : 42,963.80 = 21,716.70 : x
2. Step 2: Convert to fraction form
   31,142.67/42,963.80 = 21,716.70/x
3. Step 3: Cross multiply
   31,142.67x = 42,963.80 × 21,716.70
4. Step 4: Simplify right side
   31,142.67x = 933,031,846.88
5. Step 5: Solve for x
   x = 933,031,846.88/31,142.67
6. Step 6: Final answer
   x = 29,959.92