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Finding the Fourth Proportional to 643.53, 965.44 and 204.81

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Solution

The fourth proportional to 643.53, 965.44 and 204.81 is: 307.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.53 : 965.44 = 204.81 : x
  2. Step 2: Convert to fraction form
    643.53/965.44 = 204.81/x
  3. Step 3: Cross multiply
    643.53x = 965.44 × 204.81
  4. Step 4: Simplify right side
    643.53x = 197,725.92
  5. Step 5: Solve for x
    x = 197,725.92/643.53
  6. Step 6: Final answer
    x = 307.25

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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.