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Finding the Fourth Proportional to 520.30, 779.55 and 439.30

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Solution

The fourth proportional to 520.30, 779.55 and 439.30 is: 658.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.30 : 779.55 = 439.30 : x
  2. Step 2: Convert to fraction form
    520.30/779.55 = 439.30/x
  3. Step 3: Cross multiply
    520.30x = 779.55 × 439.30
  4. Step 4: Simplify right side
    520.30x = 342,456.32
  5. Step 5: Solve for x
    x = 342,456.32/520.30
  6. Step 6: Final answer
    x = 658.19

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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.