Finding the Third Proportional to 19,768 and 42,128

Step by Step Solution

1. Step 1: Write the proportion equation
   19,768 : 42,128 = 42,128 : x
2. Step 2: Convert to fraction form
   19,768/42,128 = 42,128/x
3. Step 3: Cross multiply
   19,768x = 42,128 × 42,128
4. Step 4: Simplify right side
   19,768x = 1,774,768,384
5. Step 5: Solve for x
   x = 1,774,768,384/19,768
6. Step 6: Final answer
   x = 89,779.87