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Finding the Fourth Proportional to 643.58, 965.40 and 424.64

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Solution

The fourth proportional to 643.58, 965.40 and 424.64 is: 636.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.58 : 965.40 = 424.64 : x
  2. Step 2: Convert to fraction form
    643.58/965.40 = 424.64/x
  3. Step 3: Cross multiply
    643.58x = 965.40 × 424.64
  4. Step 4: Simplify right side
    643.58x = 409,947.46
  5. Step 5: Solve for x
    x = 409,947.46/643.58
  6. Step 6: Final answer
    x = 636.98

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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.