Finding the Fourth Proportional to 13,145.23, 18,139.98 and 7,837.30

Step by Step Solution

1. Step 1: Write the proportion equation
   13,145.23 : 18,139.98 = 7,837.30 : x
2. Step 2: Convert to fraction form
   13,145.23/18,139.98 = 7,837.30/x
3. Step 3: Cross multiply
   13,145.23x = 18,139.98 × 7,837.30
4. Step 4: Simplify right side
   13,145.23x = 142,168,465.25
5. Step 5: Solve for x
   x = 142,168,465.25/13,145.23
6. Step 6: Final answer
   x = 10,815.21