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Finding the Fourth Proportional to 487.50, 672.72 and 290.90

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Solution

The fourth proportional to 487.50, 672.72 and 290.90 is: 401.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    487.50 : 672.72 = 290.90 : x
  2. Step 2: Convert to fraction form
    487.50/672.72 = 290.90/x
  3. Step 3: Cross multiply
    487.50x = 672.72 × 290.90
  4. Step 4: Simplify right side
    487.50x = 195,694.25
  5. Step 5: Solve for x
    x = 195,694.25/487.50
  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.