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Finding the Fourth Proportional to 278.80, 418.65 and 202.30

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Solution

The fourth proportional to 278.80, 418.65 and 202.30 is: 303.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.80 : 418.65 = 202.30 : x
  2. Step 2: Convert to fraction form
    278.80/418.65 = 202.30/x
  3. Step 3: Cross multiply
    278.80x = 418.65 × 202.30
  4. Step 4: Simplify right side
    278.80x = 84,692.90
  5. Step 5: Solve for x
    x = 84,692.90/278.80
  6. Step 6: Final answer
    x = 303.78

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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.