Finding the Fourth Proportional to 1,431.41, 1,974.17 and 1,211.09

Step by Step Solution

1. Step 1: Write the proportion equation
   1,431.41 : 1,974.17 = 1,211.09 : x
2. Step 2: Convert to fraction form
   1,431.41/1,974.17 = 1,211.09/x
3. Step 3: Cross multiply
   1,431.41x = 1,974.17 × 1,211.09
4. Step 4: Simplify right side
   1,431.41x = 2,390,890.70
5. Step 5: Solve for x
   x = 2,390,890.70/1,431.41
6. Step 6: Final answer
   x = 1,670.31