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Finding the Fourth Proportional to 319.64, 440.25 and 280.22

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Solution

The fourth proportional to 319.64, 440.25 and 280.22 is: 385.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.64 : 440.25 = 280.22 : x
  2. Step 2: Convert to fraction form
    319.64/440.25 = 280.22/x
  3. Step 3: Cross multiply
    319.64x = 440.25 × 280.22
  4. Step 4: Simplify right side
    319.64x = 123,366.86
  5. Step 5: Solve for x
    x = 123,366.86/319.64
  6. Step 6: Final answer
    x = 385.96

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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.