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Finding the Fourth Proportional to 496.80, 685.20 and 319.68

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Solution

The fourth proportional to 496.80, 685.20 and 319.68 is: 440.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    496.80 : 685.20 = 319.68 : x
  2. Step 2: Convert to fraction form
    496.80/685.20 = 319.68/x
  3. Step 3: Cross multiply
    496.80x = 685.20 × 319.68
  4. Step 4: Simplify right side
    496.80x = 219,044.74
  5. Step 5: Solve for x
    x = 219,044.74/496.80
  6. Step 6: Final answer
    x = 440.91

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.