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Finding the Fourth Proportional to 643.20, 965.28 and 296.64

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Solution

The fourth proportional to 643.20, 965.28 and 296.64 is: 445.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.20 : 965.28 = 296.64 : x
  2. Step 2: Convert to fraction form
    643.20/965.28 = 296.64/x
  3. Step 3: Cross multiply
    643.20x = 965.28 × 296.64
  4. Step 4: Simplify right side
    643.20x = 286,340.66
  5. Step 5: Solve for x
    x = 286,340.66/643.20
  6. Step 6: Final answer
    x = 445.18

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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.