Finding the Third Proportional to 10,578 and 12,090

Step by Step Solution

1. Step 1: Write the proportion equation
   10,578 : 12,090 = 12,090 : x
2. Step 2: Convert to fraction form
   10,578/12,090 = 12,090/x
3. Step 3: Cross multiply
   10,578x = 12,090 × 12,090
4. Step 4: Simplify right side
   10,578x = 146,168,100
5. Step 5: Solve for x
   x = 146,168,100/10,578
6. Step 6: Final answer
   x = 13,818.12