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Finding the Fourth Proportional to 319.20, 440.63 and 208.79

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Solution

The fourth proportional to 319.20, 440.63 and 208.79 is: 288.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.20 : 440.63 = 208.79 : x
  2. Step 2: Convert to fraction form
    319.20/440.63 = 208.79/x
  3. Step 3: Cross multiply
    319.20x = 440.63 × 208.79
  4. Step 4: Simplify right side
    319.20x = 91,999.14
  5. Step 5: Solve for x
    x = 91,999.14/319.20
  6. Step 6: Final answer
    x = 288.22

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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.