Finding the Third Proportional to 277.50 and 388.31

Step by Step Solution

1. Step 1: Write the proportion equation
   277.50 : 388.31 = 388.31 : x
2. Step 2: Convert to fraction form
   277.50/388.31 = 388.31/x
3. Step 3: Cross multiply
   277.50x = 388.31 × 388.31
4. Step 4: Simplify right side
   277.50x = 150,786.60
5. Step 5: Solve for x
   x = 150,786.60/277.50
6. Step 6: Final answer
   x = 543.38