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Finding the Fourth Proportional to 643.81, 965.54 and 253.82

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Solution

The fourth proportional to 643.81, 965.54 and 253.82 is: 380.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.81 : 965.54 = 253.82 : x
  2. Step 2: Convert to fraction form
    643.81/965.54 = 253.82/x
  3. Step 3: Cross multiply
    643.81x = 965.54 × 253.82
  4. Step 4: Simplify right side
    643.81x = 245,073.36
  5. Step 5: Solve for x
    x = 245,073.36/643.81
  6. Step 6: Final answer
    x = 380.66

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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.