Finding the Third Proportional to 39,878.58 and 87,138.28

Step by Step Solution

1. Step 1: Write the proportion equation
   39,878.58 : 87,138.28 = 87,138.28 : x
2. Step 2: Convert to fraction form
   39,878.58/87,138.28 = 87,138.28/x
3. Step 3: Cross multiply
   39,878.58x = 87,138.28 × 87,138.28
4. Step 4: Simplify right side
   39,878.58x = 7,593,080,059.20
5. Step 5: Solve for x
   x = 7,593,080,059.20/39,878.58
6. Step 6: Final answer
   x = 190,404.98