Finding the Fourth Proportional to 1,076.61, 1,613.72 and 613.36

Step by Step Solution

1. Step 1: Write the proportion equation
   1,076.61 : 1,613.72 = 613.36 : x
2. Step 2: Convert to fraction form
   1,076.61/1,613.72 = 613.36/x
3. Step 3: Cross multiply
   1,076.61x = 1,613.72 × 613.36
4. Step 4: Simplify right side
   1,076.61x = 989,799.93
5. Step 5: Solve for x
   x = 989,799.93/1,076.61
6. Step 6: Final answer
   x = 919.37