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Finding the Fourth Proportional to 491.72, 679.86 and 487.88

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Solution

The fourth proportional to 491.72, 679.86 and 487.88 is: 674.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    491.72 : 679.86 = 487.88 : x
  2. Step 2: Convert to fraction form
    491.72/679.86 = 487.88/x
  3. Step 3: Cross multiply
    491.72x = 679.86 × 487.88
  4. Step 4: Simplify right side
    491.72x = 331,690.10
  5. Step 5: Solve for x
    x = 331,690.10/491.72
  6. Step 6: Final answer
    x = 674.55

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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.