Finding the Third Proportional to 13,410 and 31,878

Step by Step Solution

1. Step 1: Write the proportion equation
   13,410 : 31,878 = 31,878 : x
2. Step 2: Convert to fraction form
   13,410/31,878 = 31,878/x
3. Step 3: Cross multiply
   13,410x = 31,878 × 31,878
4. Step 4: Simplify right side
   13,410x = 1,016,206,884
5. Step 5: Solve for x
   x = 1,016,206,884/13,410
6. Step 6: Final answer
   x = 75,779.78