Finding the Fourth Proportional to 13,978.38, 19,290.11 and 7,690.62

Step by Step Solution

1. Step 1: Write the proportion equation
   13,978.38 : 19,290.11 = 7,690.62 : x
2. Step 2: Convert to fraction form
   13,978.38/19,290.11 = 7,690.62/x
3. Step 3: Cross multiply
   13,978.38x = 19,290.11 × 7,690.62
4. Step 4: Simplify right side
   13,978.38x = 148,352,867.32
5. Step 5: Solve for x
   x = 148,352,867.32/13,978.38
6. Step 6: Final answer
   x = 10,613.02