Finding the Third Proportional to 53,144 and 78,690

Step by Step Solution

1. Step 1: Write the proportion equation
   53,144 : 78,690 = 78,690 : x
2. Step 2: Convert to fraction form
   53,144/78,690 = 78,690/x
3. Step 3: Cross multiply
   53,144x = 78,690 × 78,690
4. Step 4: Simplify right side
   53,144x = 6,192,116,100
5. Step 5: Solve for x
   x = 6,192,116,100/53,144
6. Step 6: Final answer
   x = 116,515.81