Finding the Third Proportional to 42,820 and 90,255

Step by Step Solution

1. Step 1: Write the proportion equation
   42,820 : 90,255 = 90,255 : x
2. Step 2: Convert to fraction form
   42,820/90,255 = 90,255/x
3. Step 3: Cross multiply
   42,820x = 90,255 × 90,255
4. Step 4: Simplify right side
   42,820x = 8,145,965,025
5. Step 5: Solve for x
   x = 8,145,965,025/42,820
6. Step 6: Final answer
   x = 190,237.39