Finding the Fourth Proportional to 9,315.14, 12,855.93 and 5,123.30

Step by Step Solution

1. Step 1: Write the proportion equation
   9,315.14 : 12,855.93 = 5,123.30 : x
2. Step 2: Convert to fraction form
   9,315.14/12,855.93 = 5,123.30/x
3. Step 3: Cross multiply
   9,315.14x = 12,855.93 × 5,123.30
4. Step 4: Simplify right side
   9,315.14x = 65,864,786.17
5. Step 5: Solve for x
   x = 65,864,786.17/9,315.14
6. Step 6: Final answer
   x = 7,070.72