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Finding the Fourth Proportional to 319.21, 440.23 and 207.20

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Solution

The fourth proportional to 319.21, 440.23 and 207.20 is: 285.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.21 : 440.23 = 207.20 : x
  2. Step 2: Convert to fraction form
    319.21/440.23 = 207.20/x
  3. Step 3: Cross multiply
    319.21x = 440.23 × 207.20
  4. Step 4: Simplify right side
    319.21x = 91,215.66
  5. Step 5: Solve for x
    x = 91,215.66/319.21
  6. Step 6: Final answer
    x = 285.75

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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.