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Finding the Fourth Proportional to 385.25, 577.88 and 128.75

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Solution

The fourth proportional to 385.25, 577.88 and 128.75 is: 193.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    385.25 : 577.88 = 128.75 : x
  2. Step 2: Convert to fraction form
    385.25/577.88 = 128.75/x
  3. Step 3: Cross multiply
    385.25x = 577.88 × 128.75
  4. Step 4: Simplify right side
    385.25x = 74,402.05
  5. Step 5: Solve for x
    x = 74,402.05/385.25
  6. Step 6: Final answer
    x = 193.13

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Double scale
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Similar ratio
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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.