Finding the Third Proportional to 21,012 and 31,680

Step by Step Solution

1. Step 1: Write the proportion equation
   21,012 : 31,680 = 31,680 : x
2. Step 2: Convert to fraction form
   21,012/31,680 = 31,680/x
3. Step 3: Cross multiply
   21,012x = 31,680 × 31,680
4. Step 4: Simplify right side
   21,012x = 1,003,622,400
5. Step 5: Solve for x
   x = 1,003,622,400/21,012
6. Step 6: Final answer
   x = 47,764.25