Finding the Third Proportional to 211,606 and 287,064

Step by Step Solution

1. Step 1: Write the proportion equation
   211,606 : 287,064 = 287,064 : x
2. Step 2: Convert to fraction form
   211,606/287,064 = 287,064/x
3. Step 3: Cross multiply
   211,606x = 287,064 × 287,064
4. Step 4: Simplify right side
   211,606x = 82,405,740,096
5. Step 5: Solve for x
   x = 82,405,740,096/211,606
6. Step 6: Final answer
   x = 389,430.07