Finding the Fourth Proportional to 12,300, 18,420.72 and 7,090.08

Step by Step Solution

1. Step 1: Write the proportion equation
   12,300 : 18,420.72 = 7,090.08 : x
2. Step 2: Convert to fraction form
   12,300/18,420.72 = 7,090.08/x
3. Step 3: Cross multiply
   12,300x = 18,420.72 × 7,090.08
4. Step 4: Simplify right side
   12,300x = 130,604,378.46
5. Step 5: Solve for x
   x = 130,604,378.46/12,300
6. Step 6: Final answer
   x = 10,618.24