Finding the Fourth Proportional to 13,223.34, 19,828.71 and 7,678.40

Step by Step Solution

1. Step 1: Write the proportion equation
   13,223.34 : 19,828.71 = 7,678.40 : x
2. Step 2: Convert to fraction form
   13,223.34/19,828.71 = 7,678.40/x
3. Step 3: Cross multiply
   13,223.34x = 19,828.71 × 7,678.40
4. Step 4: Simplify right side
   13,223.34x = 152,252,667.72
5. Step 5: Solve for x
   x = 152,252,667.72/13,223.34
6. Step 6: Final answer
   x = 11,513.93