Finding the Fourth Proportional to 13,978.35, 19,289.70 and 7,690.71

Step by Step Solution

1. Step 1: Write the proportion equation
   13,978.35 : 19,289.70 = 7,690.71 : x
2. Step 2: Convert to fraction form
   13,978.35/19,289.70 = 7,690.71/x
3. Step 3: Cross multiply
   13,978.35x = 19,289.70 × 7,690.71
4. Step 4: Simplify right side
   13,978.35x = 148,351,488.69
5. Step 5: Solve for x
   x = 148,351,488.69/13,978.35
6. Step 6: Final answer
   x = 10,612.95