Finding the Fourth Proportional to 12,948.72, 19,390.14 and 8,559.60

Step by Step Solution

1. Step 1: Write the proportion equation
   12,948.72 : 19,390.14 = 8,559.60 : x
2. Step 2: Convert to fraction form
   12,948.72/19,390.14 = 8,559.60/x
3. Step 3: Cross multiply
   12,948.72x = 19,390.14 × 8,559.60
4. Step 4: Simplify right side
   12,948.72x = 165,971,842.34
5. Step 5: Solve for x
   x = 165,971,842.34/12,948.72
6. Step 6: Final answer
   x = 12,817.63