Finding the Fourth Proportional to 42,711.26, 64,105.95 and 21,665.87

Step by Step Solution

1. Step 1: Write the proportion equation
   42,711.26 : 64,105.95 = 21,665.87 : x
2. Step 2: Convert to fraction form
   42,711.26/64,105.95 = 21,665.87/x
3. Step 3: Cross multiply
   42,711.26x = 64,105.95 × 21,665.87
4. Step 4: Simplify right side
   42,711.26x = 1,388,910,858.40
5. Step 5: Solve for x
   x = 1,388,910,858.40/42,711.26
6. Step 6: Final answer
   x = 32,518.62