Finding the Fourth Proportional to 1,172.35, 1,760.55 and 828.10

Step by Step Solution

1. Step 1: Write the proportion equation
   1,172.35 : 1,760.55 = 828.10 : x
2. Step 2: Convert to fraction form
   1,172.35/1,760.55 = 828.10/x
3. Step 3: Cross multiply
   1,172.35x = 1,760.55 × 828.10
4. Step 4: Simplify right side
   1,172.35x = 1,457,911.46
5. Step 5: Solve for x
   x = 1,457,911.46/1,172.35
6. Step 6: Final answer
   x = 1,243.58