Finding the Third Proportional to 10,213 and 20,858

Step by Step Solution

1. Step 1: Write the proportion equation
   10,213 : 20,858 = 20,858 : x
2. Step 2: Convert to fraction form
   10,213/20,858 = 20,858/x
3. Step 3: Cross multiply
   10,213x = 20,858 × 20,858
4. Step 4: Simplify right side
   10,213x = 435,056,164
5. Step 5: Solve for x
   x = 435,056,164/10,213
6. Step 6: Final answer
   x = 42,598.27