Finding the Third Proportional to 280,390 and 615,064

Step by Step Solution

1. Step 1: Write the proportion equation
   280,390 : 615,064 = 615,064 : x
2. Step 2: Convert to fraction form
   280,390/615,064 = 615,064/x
3. Step 3: Cross multiply
   280,390x = 615,064 × 615,064
4. Step 4: Simplify right side
   280,390x = 378,303,724,096
5. Step 5: Solve for x
   x = 378,303,724,096/280,390
6. Step 6: Final answer
   x = 1,349,205.48