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Finding the Fourth Proportional to 513.39, 770.19 and 256.89

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Solution

The fourth proportional to 513.39, 770.19 and 256.89 is: 385.39

Step by Step Solution

  1. Step 1: Write the proportion equation
    513.39 : 770.19 = 256.89 : x
  2. Step 2: Convert to fraction form
    513.39/770.19 = 256.89/x
  3. Step 3: Cross multiply
    513.39x = 770.19 × 256.89
  4. Step 4: Simplify right side
    513.39x = 197,854.11
  5. Step 5: Solve for x
    x = 197,854.11/513.39
  6. Step 6: Final answer
    x = 385.39

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Half scale
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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.