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Finding the Fourth Proportional to 519.80, 779.05 and 259.87

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Solution

The fourth proportional to 519.80, 779.05 and 259.87 is: 389.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    519.80 : 779.05 = 259.87 : x
  2. Step 2: Convert to fraction form
    519.80/779.05 = 259.87/x
  3. Step 3: Cross multiply
    519.80x = 779.05 × 259.87
  4. Step 4: Simplify right side
    519.80x = 202,452.05
  5. Step 5: Solve for x
    x = 202,452.05/519.80
  6. Step 6: Final answer
    x = 389.48

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Double scale
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Similar ratio
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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.