Finding the Third Proportional to 917,870 and 1,290,280

Step by Step Solution

1. Step 1: Write the proportion equation
   917,870 : 1,290,280 = 1,290,280 : x
2. Step 2: Convert to fraction form
   917,870/1,290,280 = 1,290,280/x
3. Step 3: Cross multiply
   917,870x = 1,290,280 × 1,290,280
4. Step 4: Simplify right side
   917,870x = 1,664,822,478,400
5. Step 5: Solve for x
   x = 1,664,822,478,400/917,870
6. Step 6: Final answer
   x = 1,813,788.97