Finding the Fourth Proportional to 1,434.81, 2,155.82 and 915.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,434.81 : 2,155.82 = 915.05 : x
2. Step 2: Convert to fraction form
   1,434.81/2,155.82 = 915.05/x
3. Step 3: Cross multiply
   1,434.81x = 2,155.82 × 915.05
4. Step 4: Simplify right side
   1,434.81x = 1,972,667.74
5. Step 5: Solve for x
   x = 1,972,667.74/1,434.81
6. Step 6: Final answer
   x = 1,374.86