Finding the Fourth Proportional to 1,421.34, 1,961.46 and 823.87

Step by Step Solution

1. Step 1: Write the proportion equation
   1,421.34 : 1,961.46 = 823.87 : x
2. Step 2: Convert to fraction form
   1,421.34/1,961.46 = 823.87/x
3. Step 3: Cross multiply
   1,421.34x = 1,961.46 × 823.87
4. Step 4: Simplify right side
   1,421.34x = 1,615,998.04
5. Step 5: Solve for x
   x = 1,615,998.04/1,421.34
6. Step 6: Final answer
   x = 1,136.96