Finding the Fourth Proportional to 9,620.70, 13,279.59 and 5,643.42

Step by Step Solution

1. Step 1: Write the proportion equation
   9,620.70 : 13,279.59 = 5,643.42 : x
2. Step 2: Convert to fraction form
   9,620.70/13,279.59 = 5,643.42/x
3. Step 3: Cross multiply
   9,620.70x = 13,279.59 × 5,643.42
4. Step 4: Simplify right side
   9,620.70x = 74,942,303.80
5. Step 5: Solve for x
   x = 74,942,303.80/9,620.70
6. Step 6: Final answer
   x = 7,789.69