Finding the Fourth Proportional to 1,113.27, 1,670.69 and 821.53

Step by Step Solution

1. Step 1: Write the proportion equation
   1,113.27 : 1,670.69 = 821.53 : x
2. Step 2: Convert to fraction form
   1,113.27/1,670.69 = 821.53/x
3. Step 3: Cross multiply
   1,113.27x = 1,670.69 × 821.53
4. Step 4: Simplify right side
   1,113.27x = 1,372,513.67
5. Step 5: Solve for x
   x = 1,372,513.67/1,113.27
6. Step 6: Final answer
   x = 1,232.87