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Finding the Fourth Proportional to 487.32, 672.40 and 290.89

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Solution

The fourth proportional to 487.32, 672.40 and 290.89 is: 401.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.32 : 672.40 = 290.89 : x
  2. Step 2: Convert to fraction form
    487.32/672.40 = 290.89/x
  3. Step 3: Cross multiply
    487.32x = 672.40 × 290.89
  4. Step 4: Simplify right side
    487.32x = 195,595.64
  5. Step 5: Solve for x
    x = 195,595.64/487.32
  6. Step 6: Final answer
    x = 401.37

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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.