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Finding the Fourth Proportional to 279.38, 418.80 and 135.20

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Solution

The fourth proportional to 279.38, 418.80 and 135.20 is: 202.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.38 : 418.80 = 135.20 : x
  2. Step 2: Convert to fraction form
    279.38/418.80 = 135.20/x
  3. Step 3: Cross multiply
    279.38x = 418.80 × 135.20
  4. Step 4: Simplify right side
    279.38x = 56,621.76
  5. Step 5: Solve for x
    x = 56,621.76/279.38
  6. Step 6: Final answer
    x = 202.67

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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.