Finding the Fourth Proportional to 13,978.86, 19,290.38 and 7,691.22

Step by Step Solution

1. Step 1: Write the proportion equation
   13,978.86 : 19,290.38 = 7,691.22 : x
2. Step 2: Convert to fraction form
   13,978.86/19,290.38 = 7,691.22/x
3. Step 3: Cross multiply
   13,978.86x = 19,290.38 × 7,691.22
4. Step 4: Simplify right side
   13,978.86x = 148,366,556.46
5. Step 5: Solve for x
   x = 148,366,556.46/13,978.86
6. Step 6: Final answer
   x = 10,613.64