Finding the Fourth Proportional to 70,436.43, 105,653.12 and 17,128.71

Step by Step Solution

1. Step 1: Write the proportion equation
   70,436.43 : 105,653.12 = 17,128.71 : x
2. Step 2: Convert to fraction form
   70,436.43/105,653.12 = 17,128.71/x
3. Step 3: Cross multiply
   70,436.43x = 105,653.12 × 17,128.71
4. Step 4: Simplify right side
   70,436.43x = 1,809,701,567.43
5. Step 5: Solve for x
   x = 1,809,701,567.43/70,436.43
6. Step 6: Final answer
   x = 25,692.69