Finding the Fourth Proportional to 1,423.64, 1,964.34 and 899.40

Step by Step Solution

1. Step 1: Write the proportion equation
   1,423.64 : 1,964.34 = 899.40 : x
2. Step 2: Convert to fraction form
   1,423.64/1,964.34 = 899.40/x
3. Step 3: Cross multiply
   1,423.64x = 1,964.34 × 899.40
4. Step 4: Simplify right side
   1,423.64x = 1,766,727.40
5. Step 5: Solve for x
   x = 1,766,727.40/1,423.64
6. Step 6: Final answer
   x = 1,240.99