Finding the Third Proportional to 642,320 and 980,240

Step by Step Solution

1. Step 1: Write the proportion equation
   642,320 : 980,240 = 980,240 : x
2. Step 2: Convert to fraction form
   642,320/980,240 = 980,240/x
3. Step 3: Cross multiply
   642,320x = 980,240 × 980,240
4. Step 4: Simplify right side
   642,320x = 960,870,457,600
5. Step 5: Solve for x
   x = 960,870,457,600/642,320
6. Step 6: Final answer
   x = 1,495,937.32