Finding the Fourth Proportional to 28,638.42, 42,940.89 and 10,870.26

Step by Step Solution

1. Step 1: Write the proportion equation
   28,638.42 : 42,940.89 = 10,870.26 : x
2. Step 2: Convert to fraction form
   28,638.42/42,940.89 = 10,870.26/x
3. Step 3: Cross multiply
   28,638.42x = 42,940.89 × 10,870.26
4. Step 4: Simplify right side
   28,638.42x = 466,778,638.93
5. Step 5: Solve for x
   x = 466,778,638.93/28,638.42
6. Step 6: Final answer
   x = 16,299.04