Finding the Fourth Proportional to 1,638.66, 2,261.59 and 930.69

Step by Step Solution

1. Step 1: Write the proportion equation
   1,638.66 : 2,261.59 = 930.69 : x
2. Step 2: Convert to fraction form
   1,638.66/2,261.59 = 930.69/x
3. Step 3: Cross multiply
   1,638.66x = 2,261.59 × 930.69
4. Step 4: Simplify right side
   1,638.66x = 2,104,839.20
5. Step 5: Solve for x
   x = 2,104,839.20/1,638.66
6. Step 6: Final answer
   x = 1,284.49