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Finding the Fourth Proportional to 518.56, 777.81 and 287.56

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Solution

The fourth proportional to 518.56, 777.81 and 287.56 is: 431.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.56 : 777.81 = 287.56 : x
  2. Step 2: Convert to fraction form
    518.56/777.81 = 287.56/x
  3. Step 3: Cross multiply
    518.56x = 777.81 × 287.56
  4. Step 4: Simplify right side
    518.56x = 223,667.04
  5. Step 5: Solve for x
    x = 223,667.04/518.56
  6. Step 6: Final answer
    x = 431.32

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.