Finding the Fourth Proportional to 42,991.76, 64,504.20 and 16,715

Step by Step Solution

1. Step 1: Write the proportion equation
   42,991.76 : 64,504.20 = 16,715 : x
2. Step 2: Convert to fraction form
   42,991.76/64,504.20 = 16,715/x
3. Step 3: Cross multiply
   42,991.76x = 64,504.20 × 16,715
4. Step 4: Simplify right side
   42,991.76x = 1,078,187,703
5. Step 5: Solve for x
   x = 1,078,187,703/42,991.76
6. Step 6: Final answer
   x = 25,078.94