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Finding the Fourth Proportional to 518.76, 715.89 and 285.90

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Solution

The fourth proportional to 518.76, 715.89 and 285.90 is: 394.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    518.76 : 715.89 = 285.90 : x
  2. Step 2: Convert to fraction form
    518.76/715.89 = 285.90/x
  3. Step 3: Cross multiply
    518.76x = 715.89 × 285.90
  4. Step 4: Simplify right side
    518.76x = 204,672.95
  5. Step 5: Solve for x
    x = 204,672.95/518.76
  6. Step 6: Final answer
    x = 394.54

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Find fourth proportional to 259.38, 357.95 and 142.95
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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 (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.