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Finding the Fourth Proportional to 487.25, 672.42 and 280.25

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Solution

The fourth proportional to 487.25, 672.42 and 280.25 is: 386.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.25 : 672.42 = 280.25 : x
  2. Step 2: Convert to fraction form
    487.25/672.42 = 280.25/x
  3. Step 3: Cross multiply
    487.25x = 672.42 × 280.25
  4. Step 4: Simplify right side
    487.25x = 188,445.71
  5. Step 5: Solve for x
    x = 188,445.71/487.25
  6. Step 6: Final answer
    x = 386.75

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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.