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Finding the Fourth Proportional to 518.20, 777.49 and 258.18

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Solution

The fourth proportional to 518.20, 777.49 and 258.18 is: 387.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.20 : 777.49 = 258.18 : x
  2. Step 2: Convert to fraction form
    518.20/777.49 = 258.18/x
  3. Step 3: Cross multiply
    518.20x = 777.49 × 258.18
  4. Step 4: Simplify right side
    518.20x = 200,730.75
  5. Step 5: Solve for x
    x = 200,730.75/518.20
  6. Step 6: Final answer
    x = 387.36

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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.