Finding the Fourth Proportional to 1,528.82, 2,109.76 and 830.20

Step by Step Solution

1. Step 1: Write the proportion equation
   1,528.82 : 2,109.76 = 830.20 : x
2. Step 2: Convert to fraction form
   1,528.82/2,109.76 = 830.20/x
3. Step 3: Cross multiply
   1,528.82x = 2,109.76 × 830.20
4. Step 4: Simplify right side
   1,528.82x = 1,751,522.75
5. Step 5: Solve for x
   x = 1,751,522.75/1,528.82
6. Step 6: Final answer
   x = 1,145.67