Finding the Fourth Proportional to 28,104.69, 42,161.61 and 13,126.79

Step by Step Solution

1. Step 1: Write the proportion equation
   28,104.69 : 42,161.61 = 13,126.79 : x
2. Step 2: Convert to fraction form
   28,104.69/42,161.61 = 13,126.79/x
3. Step 3: Cross multiply
   28,104.69x = 42,161.61 × 13,126.79
4. Step 4: Simplify right side
   28,104.69x = 553,446,389.72
5. Step 5: Solve for x
   x = 553,446,389.72/28,104.69
6. Step 6: Final answer
   x = 19,692.31