Finding the Fourth Proportional to 31,131.50, 42,958.20 and 19,200.20

Step by Step Solution

1. Step 1: Write the proportion equation
   31,131.50 : 42,958.20 = 19,200.20 : x
2. Step 2: Convert to fraction form
   31,131.50/42,958.20 = 19,200.20/x
3. Step 3: Cross multiply
   31,131.50x = 42,958.20 × 19,200.20
4. Step 4: Simplify right side
   31,131.50x = 824,806,031.64
5. Step 5: Solve for x
   x = 824,806,031.64/31,131.50
6. Step 6: Final answer
   x = 26,494.26