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Finding the Fourth Proportional to 321.35, 480.87 and 287.55

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Solution

The fourth proportional to 321.35, 480.87 and 287.55 is: 430.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    321.35 : 480.87 = 287.55 : x
  2. Step 2: Convert to fraction form
    321.35/480.87 = 287.55/x
  3. Step 3: Cross multiply
    321.35x = 480.87 × 287.55
  4. Step 4: Simplify right side
    321.35x = 138,274.17
  5. Step 5: Solve for x
    x = 138,274.17/321.35
  6. Step 6: Final answer
    x = 430.30

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.