Finding the Fourth Proportional to 53,647.37, 80,470.67 and 13,120.37

Step by Step Solution

1. Step 1: Write the proportion equation
   53,647.37 : 80,470.67 = 13,120.37 : x
2. Step 2: Convert to fraction form
   53,647.37/80,470.67 = 13,120.37/x
3. Step 3: Cross multiply
   53,647.37x = 80,470.67 × 13,120.37
4. Step 4: Simplify right side
   53,647.37x = 1,055,804,496.59
5. Step 5: Solve for x
   x = 1,055,804,496.59/53,647.37
6. Step 6: Final answer
   x = 19,680.45