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Finding the Fourth Proportional to 487.48, 672.78 and 280.52

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Solution

The fourth proportional to 487.48, 672.78 and 280.52 is: 387.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.48 : 672.78 = 280.52 : x
  2. Step 2: Convert to fraction form
    487.48/672.78 = 280.52/x
  3. Step 3: Cross multiply
    487.48x = 672.78 × 280.52
  4. Step 4: Simplify right side
    487.48x = 188,728.25
  5. Step 5: Solve for x
    x = 188,728.25/487.48
  6. Step 6: Final answer
    x = 387.15

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.