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Finding the Fourth Proportional to 342.72, 512.89 and 280.30

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Solution

The fourth proportional to 342.72, 512.89 and 280.30 is: 419.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    342.72 : 512.89 = 280.30 : x
  2. Step 2: Convert to fraction form
    342.72/512.89 = 280.30/x
  3. Step 3: Cross multiply
    342.72x = 512.89 × 280.30
  4. Step 4: Simplify right side
    342.72x = 143,764.49
  5. Step 5: Solve for x
    x = 143,764.49/342.72
  6. Step 6: Final answer
    x = 419.48

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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.