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Finding the Fourth Proportional to 643.49, 965.20 and 181.30

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Solution

The fourth proportional to 643.49, 965.20 and 181.30 is: 271.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.49 : 965.20 = 181.30 : x
  2. Step 2: Convert to fraction form
    643.49/965.20 = 181.30/x
  3. Step 3: Cross multiply
    643.49x = 965.20 × 181.30
  4. Step 4: Simplify right side
    643.49x = 174,990.76
  5. Step 5: Solve for x
    x = 174,990.76/643.49
  6. Step 6: Final answer
    x = 271.94

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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.