Finding the Third Proportional to 310,878 and 456,111

Step by Step Solution

1. Step 1: Write the proportion equation
   310,878 : 456,111 = 456,111 : x
2. Step 2: Convert to fraction form
   310,878/456,111 = 456,111/x
3. Step 3: Cross multiply
   310,878x = 456,111 × 456,111
4. Step 4: Simplify right side
   310,878x = 208,037,244,321
5. Step 5: Solve for x
   x = 208,037,244,321/310,878
6. Step 6: Final answer
   x = 669,192.56