Finding the Fourth Proportional to 42,128.21, 63,143.72 and 15,816.17

Step by Step Solution

1. Step 1: Write the proportion equation
   42,128.21 : 63,143.72 = 15,816.17 : x
2. Step 2: Convert to fraction form
   42,128.21/63,143.72 = 15,816.17/x
3. Step 3: Cross multiply
   42,128.21x = 63,143.72 × 15,816.17
4. Step 4: Simplify right side
   42,128.21x = 998,691,730.87
5. Step 5: Solve for x
   x = 998,691,730.87/42,128.21
6. Step 6: Final answer
   x = 23,706.01