Finding the Third Proportional to 678,010.50 and 991,561.50

Step by Step Solution

1. Step 1: Write the proportion equation
   678,010.50 : 991,561.50 = 991,561.50 : x
2. Step 2: Convert to fraction form
   678,010.50/991,561.50 = 991,561.50/x
3. Step 3: Cross multiply
   678,010.50x = 991,561.50 × 991,561.50
4. Step 4: Simplify right side
   678,010.50x = 983,194,208,282.25
5. Step 5: Solve for x
   x = 983,194,208,282.25/678,010.50
6. Step 6: Final answer
   x = 1,450,116.49