Finding the Third Proportional to 20,380 and 42,070

Step by Step Solution

1. Step 1: Write the proportion equation
   20,380 : 42,070 = 42,070 : x
2. Step 2: Convert to fraction form
   20,380/42,070 = 42,070/x
3. Step 3: Cross multiply
   20,380x = 42,070 × 42,070
4. Step 4: Simplify right side
   20,380x = 1,769,884,900
5. Step 5: Solve for x
   x = 1,769,884,900/20,380
6. Step 6: Final answer
   x = 86,844.21