Finding the Fourth Proportional to 2,821.78, 4,231.02 and 972.10

Step by Step Solution

1. Step 1: Write the proportion equation
   2,821.78 : 4,231.02 = 972.10 : x
2. Step 2: Convert to fraction form
   2,821.78/4,231.02 = 972.10/x
3. Step 3: Cross multiply
   2,821.78x = 4,231.02 × 972.10
4. Step 4: Simplify right side
   2,821.78x = 4,112,974.54
5. Step 5: Solve for x
   x = 4,112,974.54/2,821.78
6. Step 6: Final answer
   x = 1,457.58