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Finding the Fourth Proportional to 643.88, 965.59 and 205.00

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Solution

The fourth proportional to 643.88, 965.59 and 205.00 is: 307.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.88 : 965.59 = 205.00 : x
  2. Step 2: Convert to fraction form
    643.88/965.59 = 205.00/x
  3. Step 3: Cross multiply
    643.88x = 965.59 × 205.00
  4. Step 4: Simplify right side
    643.88x = 197,943.02
  5. Step 5: Solve for x
    x = 197,943.02/643.88
  6. Step 6: Final answer
    x = 307.42

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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.