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Finding the Fourth Proportional to 465.81, 643.04 and 319.20

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Solution

The fourth proportional to 465.81, 643.04 and 319.20 is: 440.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    465.81 : 643.04 = 319.20 : x
  2. Step 2: Convert to fraction form
    465.81/643.04 = 319.20/x
  3. Step 3: Cross multiply
    465.81x = 643.04 × 319.20
  4. Step 4: Simplify right side
    465.81x = 205,258.37
  5. Step 5: Solve for x
    x = 205,258.37/465.81
  6. Step 6: Final answer
    x = 440.65

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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.