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Finding the Fourth Proportional to 487.39, 672.63 and 290.87

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Solution

The fourth proportional to 487.39, 672.63 and 290.87 is: 401.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.39 : 672.63 = 290.87 : x
  2. Step 2: Convert to fraction form
    487.39/672.63 = 290.87/x
  3. Step 3: Cross multiply
    487.39x = 672.63 × 290.87
  4. Step 4: Simplify right side
    487.39x = 195,647.89
  5. Step 5: Solve for x
    x = 195,647.89/487.39
  6. Step 6: Final answer
    x = 401.42

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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.