Finding the Fourth Proportional to 1,420.21, 1,959.25 and 830.49

Step by Step Solution

1. Step 1: Write the proportion equation
   1,420.21 : 1,959.25 = 830.49 : x
2. Step 2: Convert to fraction form
   1,420.21/1,959.25 = 830.49/x
3. Step 3: Cross multiply
   1,420.21x = 1,959.25 × 830.49
4. Step 4: Simplify right side
   1,420.21x = 1,627,137.53
5. Step 5: Solve for x
   x = 1,627,137.53/1,420.21
6. Step 6: Final answer
   x = 1,145.70