Finding the Fourth Proportional to 1,615.63, 2,229.61 and 917.05

Step by Step Solution

1. Step 1: Write the proportion equation
   1,615.63 : 2,229.61 = 917.05 : x
2. Step 2: Convert to fraction form
   1,615.63/2,229.61 = 917.05/x
3. Step 3: Cross multiply
   1,615.63x = 2,229.61 × 917.05
4. Step 4: Simplify right side
   1,615.63x = 2,044,663.85
5. Step 5: Solve for x
   x = 2,044,663.85/1,615.63
6. Step 6: Final answer
   x = 1,265.55