Finding the Fourth Proportional to 3,420.56, 5,130.72 and 1,112

Step by Step Solution

1. Step 1: Write the proportion equation
   3,420.56 : 5,130.72 = 1,112 : x
2. Step 2: Convert to fraction form
   3,420.56/5,130.72 = 1,112/x
3. Step 3: Cross multiply
   3,420.56x = 5,130.72 × 1,112
4. Step 4: Simplify right side
   3,420.56x = 5,705,360.64
5. Step 5: Solve for x
   x = 5,705,360.64/3,420.56
6. Step 6: Final answer
   x = 1,667.96