Finding the Fourth Proportional to 1,200.98, 1,656.81 and 828.47

Step by Step Solution

1. Step 1: Write the proportion equation
   1,200.98 : 1,656.81 = 828.47 : x
2. Step 2: Convert to fraction form
   1,200.98/1,656.81 = 828.47/x
3. Step 3: Cross multiply
   1,200.98x = 1,656.81 × 828.47
4. Step 4: Simplify right side
   1,200.98x = 1,372,609.10
5. Step 5: Solve for x
   x = 1,372,609.10/1,200.98
6. Step 6: Final answer
   x = 1,142.91