Finding the Fourth Proportional to 1,409.07, 2,109.69 and 916.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,409.07 : 2,109.69 = 916.05 : x
2. Step 2: Convert to fraction form
   1,409.07/2,109.69 = 916.05/x
3. Step 3: Cross multiply
   1,409.07x = 2,109.69 × 916.05
4. Step 4: Simplify right side
   1,409.07x = 1,932,581.52
5. Step 5: Solve for x
   x = 1,932,581.52/1,409.07
6. Step 6: Final answer
   x = 1,371.53