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Finding the Fourth Proportional to 483.78, 667.38 and 287.20

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Solution

The fourth proportional to 483.78, 667.38 and 287.20 is: 396.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    483.78 : 667.38 = 287.20 : x
  2. Step 2: Convert to fraction form
    483.78/667.38 = 287.20/x
  3. Step 3: Cross multiply
    483.78x = 667.38 × 287.20
  4. Step 4: Simplify right side
    483.78x = 191,666.76
  5. Step 5: Solve for x
    x = 191,666.76/483.78
  6. Step 6: Final answer
    x = 396.19

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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.