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Finding the Fourth Proportional to 640.84, 961.44 and 457.68

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Solution

The fourth proportional to 640.84, 961.44 and 457.68 is: 686.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.84 : 961.44 = 457.68 : x
  2. Step 2: Convert to fraction form
    640.84/961.44 = 457.68/x
  3. Step 3: Cross multiply
    640.84x = 961.44 × 457.68
  4. Step 4: Simplify right side
    640.84x = 440,031.86
  5. Step 5: Solve for x
    x = 440,031.86/640.84
  6. Step 6: Final answer
    x = 686.65

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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.