Finding the Third Proportional to 436.78 and 916.31

Step by Step Solution

1. Step 1: Write the proportion equation
   436.78 : 916.31 = 916.31 : x
2. Step 2: Convert to fraction form
   436.78/916.31 = 916.31/x
3. Step 3: Cross multiply
   436.78x = 916.31 × 916.31
4. Step 4: Simplify right side
   436.78x = 839,628.60
5. Step 5: Solve for x
   x = 839,628.60/436.78
6. Step 6: Final answer
   x = 1,922.31