Finding the Fourth Proportional to 9,956.78, 13,739.71 and 5,707.79

Step by Step Solution

1. Step 1: Write the proportion equation
   9,956.78 : 13,739.71 = 5,707.79 : x
2. Step 2: Convert to fraction form
   9,956.78/13,739.71 = 5,707.79/x
3. Step 3: Cross multiply
   9,956.78x = 13,739.71 × 5,707.79
4. Step 4: Simplify right side
   9,956.78x = 78,423,379.34
5. Step 5: Solve for x
   x = 78,423,379.34/9,956.78
6. Step 6: Final answer
   x = 7,876.38