Finding the Third Proportional to 7,658 and 12,215.50

Step by Step Solution

1. Step 1: Write the proportion equation
   7,658 : 12,215.50 = 12,215.50 : x
2. Step 2: Convert to fraction form
   7,658/12,215.50 = 12,215.50/x
3. Step 3: Cross multiply
   7,658x = 12,215.50 × 12,215.50
4. Step 4: Simplify right side
   7,658x = 149,218,440.25
5. Step 5: Solve for x
   x = 149,218,440.25/7,658
6. Step 6: Final answer
   x = 19,485.30