Finding the Third Proportional to 15,676 and 21,290

Step by Step Solution

1. Step 1: Write the proportion equation
   15,676 : 21,290 = 21,290 : x
2. Step 2: Convert to fraction form
   15,676/21,290 = 21,290/x
3. Step 3: Cross multiply
   15,676x = 21,290 × 21,290
4. Step 4: Simplify right side
   15,676x = 453,264,100
5. Step 5: Solve for x
   x = 453,264,100/15,676
6. Step 6: Final answer
   x = 28,914.53