Finding the Fourth Proportional to 1,398.45, 1,929.97 and 902.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,398.45 : 1,929.97 = 902.12 : x
2. Step 2: Convert to fraction form
   1,398.45/1,929.97 = 902.12/x
3. Step 3: Cross multiply
   1,398.45x = 1,929.97 × 902.12
4. Step 4: Simplify right side
   1,398.45x = 1,741,064.54
5. Step 5: Solve for x
   x = 1,741,064.54/1,398.45
6. Step 6: Final answer
   x = 1,245.00