Finding the Third Proportional to 51,196 and 78,980

Step by Step Solution

1. Step 1: Write the proportion equation
   51,196 : 78,980 = 78,980 : x
2. Step 2: Convert to fraction form
   51,196/78,980 = 78,980/x
3. Step 3: Cross multiply
   51,196x = 78,980 × 78,980
4. Step 4: Simplify right side
   51,196x = 6,237,840,400
5. Step 5: Solve for x
   x = 6,237,840,400/51,196
6. Step 6: Final answer
   x = 121,842.34