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Finding the Fourth Proportional to 479.77, 721.14 and 318.49

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Solution

The fourth proportional to 479.77, 721.14 and 318.49 is: 478.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    479.77 : 721.14 = 318.49 : x
  2. Step 2: Convert to fraction form
    479.77/721.14 = 318.49/x
  3. Step 3: Cross multiply
    479.77x = 721.14 × 318.49
  4. Step 4: Simplify right side
    479.77x = 229,675.88
  5. Step 5: Solve for x
    x = 229,675.88/479.77
  6. Step 6: Final answer
    x = 478.72

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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.