Finding the Fourth Proportional to 12,970.72, 19,458.24 and 5,179.68

Step by Step Solution

1. Step 1: Write the proportion equation
   12,970.72 : 19,458.24 = 5,179.68 : x
2. Step 2: Convert to fraction form
   12,970.72/19,458.24 = 5,179.68/x
3. Step 3: Cross multiply
   12,970.72x = 19,458.24 × 5,179.68
4. Step 4: Simplify right side
   12,970.72x = 100,787,456.56
5. Step 5: Solve for x
   x = 100,787,456.56/12,970.72
6. Step 6: Final answer
   x = 7,770.38