Finding the Third Proportional to 30,870 and 67,389.75

Step by Step Solution

1. Step 1: Write the proportion equation
   30,870 : 67,389.75 = 67,389.75 : x
2. Step 2: Convert to fraction form
   30,870/67,389.75 = 67,389.75/x
3. Step 3: Cross multiply
   30,870x = 67,389.75 × 67,389.75
4. Step 4: Simplify right side
   30,870x = 4,541,378,405.06
5. Step 5: Solve for x
   x = 4,541,378,405.06/30,870
6. Step 6: Final answer
   x = 147,113.00