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Finding the Fourth Proportional to 320.88, 479.11 and 315.21

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Solution

The fourth proportional to 320.88, 479.11 and 315.21 is: 470.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    320.88 : 479.11 = 315.21 : x
  2. Step 2: Convert to fraction form
    320.88/479.11 = 315.21/x
  3. Step 3: Cross multiply
    320.88x = 479.11 × 315.21
  4. Step 4: Simplify right side
    320.88x = 151,019.48
  5. Step 5: Solve for x
    x = 151,019.48/320.88
  6. Step 6: Final answer
    x = 470.64

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.