Finding the Fourth Proportional to 31,150.80, 42,986.60 and 17,720.79

Step by Step Solution

1. Step 1: Write the proportion equation
   31,150.80 : 42,986.60 = 17,720.79 : x
2. Step 2: Convert to fraction form
   31,150.80/42,986.60 = 17,720.79/x
3. Step 3: Cross multiply
   31,150.80x = 42,986.60 × 17,720.79
4. Step 4: Simplify right side
   31,150.80x = 761,756,555.72
5. Step 5: Solve for x
   x = 761,756,555.72/31,150.80
6. Step 6: Final answer
   x = 24,453.84