Finding the Fourth Proportional to 1,659.79, 2,290.57 and 913.78

Step by Step Solution

1. Step 1: Write the proportion equation
   1,659.79 : 2,290.57 = 913.78 : x
2. Step 2: Convert to fraction form
   1,659.79/2,290.57 = 913.78/x
3. Step 3: Cross multiply
   1,659.79x = 2,290.57 × 913.78
4. Step 4: Simplify right side
   1,659.79x = 2,093,077.05
5. Step 5: Solve for x
   x = 2,093,077.05/1,659.79
6. Step 6: Final answer
   x = 1,261.05