Finding the Fourth Proportional to 1,420.27, 1,959.66 and 830.45

Step by Step Solution

1. Step 1: Write the proportion equation
   1,420.27 : 1,959.66 = 830.45 : x
2. Step 2: Convert to fraction form
   1,420.27/1,959.66 = 830.45/x
3. Step 3: Cross multiply
   1,420.27x = 1,959.66 × 830.45
4. Step 4: Simplify right side
   1,420.27x = 1,627,404.55
5. Step 5: Solve for x
   x = 1,627,404.55/1,420.27
6. Step 6: Final answer
   x = 1,145.84