Finding the Fourth Proportional to 1,111.34, 1,667.97 and 427.82

Step by Step Solution

1. Step 1: Write the proportion equation
   1,111.34 : 1,667.97 = 427.82 : x
2. Step 2: Convert to fraction form
   1,111.34/1,667.97 = 427.82/x
3. Step 3: Cross multiply
   1,111.34x = 1,667.97 × 427.82
4. Step 4: Simplify right side
   1,111.34x = 713,590.93
5. Step 5: Solve for x
   x = 713,590.93/1,111.34
6. Step 6: Final answer
   x = 642.10