Finding the Fourth Proportional to 7,123.72, 9,830.76 and 3,979.96

Step by Step Solution

1. Step 1: Write the proportion equation
   7,123.72 : 9,830.76 = 3,979.96 : x
2. Step 2: Convert to fraction form
   7,123.72/9,830.76 = 3,979.96/x
3. Step 3: Cross multiply
   7,123.72x = 9,830.76 × 3,979.96
4. Step 4: Simplify right side
   7,123.72x = 39,126,031.57
5. Step 5: Solve for x
   x = 39,126,031.57/7,123.72
6. Step 6: Final answer
   x = 5,492.36