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Finding the Fourth Proportional to 319.21, 440.68 and 208.79

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Solution

The fourth proportional to 319.21, 440.68 and 208.79 is: 288.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.21 : 440.68 = 208.79 : x
  2. Step 2: Convert to fraction form
    319.21/440.68 = 208.79/x
  3. Step 3: Cross multiply
    319.21x = 440.68 × 208.79
  4. Step 4: Simplify right side
    319.21x = 92,011.20
  5. Step 5: Solve for x
    x = 92,011.20/319.21
  6. Step 6: Final answer
    x = 288.25

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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.