Finding the Fourth Proportional to 1,112.10, 1,667.20 and 679.56

Step by Step Solution

1. Step 1: Write the proportion equation
   1,112.10 : 1,667.20 = 679.56 : x
2. Step 2: Convert to fraction form
   1,112.10/1,667.20 = 679.56/x
3. Step 3: Cross multiply
   1,112.10x = 1,667.20 × 679.56
4. Step 4: Simplify right side
   1,112.10x = 1,132,962.43
5. Step 5: Solve for x
   x = 1,132,962.43/1,112.10
6. Step 6: Final answer
   x = 1,018.76