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Finding the Fourth Proportional to 640.53, 962.15 and 479.21

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Solution

The fourth proportional to 640.53, 962.15 and 479.21 is: 719.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.53 : 962.15 = 479.21 : x
  2. Step 2: Convert to fraction form
    640.53/962.15 = 479.21/x
  3. Step 3: Cross multiply
    640.53x = 962.15 × 479.21
  4. Step 4: Simplify right side
    640.53x = 461,064.69
  5. Step 5: Solve for x
    x = 461,064.69/640.53
  6. Step 6: Final answer
    x = 719.82

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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.