Finding the Fourth Proportional to 51,643.80, 71,262.59 and 28,978.07

Step by Step Solution

1. Step 1: Write the proportion equation
   51,643.80 : 71,262.59 = 28,978.07 : x
2. Step 2: Convert to fraction form
   51,643.80/71,262.59 = 28,978.07/x
3. Step 3: Cross multiply
   51,643.80x = 71,262.59 × 28,978.07
4. Step 4: Simplify right side
   51,643.80x = 2,065,051,820.20
5. Step 5: Solve for x
   x = 2,065,051,820.20/51,643.80
6. Step 6: Final answer
   x = 39,986.44