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Finding the Fourth Proportional to 638.48, 880.48 and 490.80

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Solution

The fourth proportional to 638.48, 880.48 and 490.80 is: 676.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.48 : 880.48 = 490.80 : x
  2. Step 2: Convert to fraction form
    638.48/880.48 = 490.80/x
  3. Step 3: Cross multiply
    638.48x = 880.48 × 490.80
  4. Step 4: Simplify right side
    638.48x = 432,139.58
  5. Step 5: Solve for x
    x = 432,139.58/638.48
  6. Step 6: Final answer
    x = 676.83

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1.5x scale

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.