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Finding the Fourth Proportional to 645.42, 968.14 and 428.96

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Solution

The fourth proportional to 645.42, 968.14 and 428.96 is: 643.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.42 : 968.14 = 428.96 : x
  2. Step 2: Convert to fraction form
    645.42/968.14 = 428.96/x
  3. Step 3: Cross multiply
    645.42x = 968.14 × 428.96
  4. Step 4: Simplify right side
    645.42x = 415,293.33
  5. Step 5: Solve for x
    x = 415,293.33/645.42
  6. Step 6: Final answer
    x = 643.45

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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.