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Finding the Fourth Proportional to 979.80, 1,469.10 and 394.89

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Solution

The fourth proportional to 979.80, 1,469.10 and 394.89 is: 592.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    979.80 : 1,469.10 = 394.89 : x
  2. Step 2: Convert to fraction form
    979.80/1,469.10 = 394.89/x
  3. Step 3: Cross multiply
    979.80x = 1,469.10 × 394.89
  4. Step 4: Simplify right side
    979.80x = 580,132.90
  5. Step 5: Solve for x
    x = 580,132.90/979.80
  6. Step 6: Final answer
    x = 592.09

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Double scale
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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.