Finding the Fourth Proportional to 1,421.34, 1,962.39 and 918.12

Step by Step Solution

1. Step 1: Write the proportion equation
   1,421.34 : 1,962.39 = 918.12 : x
2. Step 2: Convert to fraction form
   1,421.34/1,962.39 = 918.12/x
3. Step 3: Cross multiply
   1,421.34x = 1,962.39 × 918.12
4. Step 4: Simplify right side
   1,421.34x = 1,801,709.51
5. Step 5: Solve for x
   x = 1,801,709.51/1,421.34
6. Step 6: Final answer
   x = 1,267.61