Finding the Fourth Proportional to 1,421.62, 1,961.61 and 800.50

Step by Step Solution

1. Step 1: Write the proportion equation
   1,421.62 : 1,961.61 = 800.50 : x
2. Step 2: Convert to fraction form
   1,421.62/1,961.61 = 800.50/x
3. Step 3: Cross multiply
   1,421.62x = 1,961.61 × 800.50
4. Step 4: Simplify right side
   1,421.62x = 1,570,268.81
5. Step 5: Solve for x
   x = 1,570,268.81/1,421.62
6. Step 6: Final answer
   x = 1,104.56