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Finding the Fourth Proportional to 643.63, 965.16 and 204.80

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Solution

The fourth proportional to 643.63, 965.16 and 204.80 is: 307.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.63 : 965.16 = 204.80 : x
  2. Step 2: Convert to fraction form
    643.63/965.16 = 204.80/x
  3. Step 3: Cross multiply
    643.63x = 965.16 × 204.80
  4. Step 4: Simplify right side
    643.63x = 197,658.92
  5. Step 5: Solve for x
    x = 197,658.92/643.63
  6. Step 6: Final answer
    x = 307.10

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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.