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Finding the Fourth Proportional to 279.72, 419.78 and 171.18

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Solution

The fourth proportional to 279.72, 419.78 and 171.18 is: 256.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.72 : 419.78 = 171.18 : x
  2. Step 2: Convert to fraction form
    279.72/419.78 = 171.18/x
  3. Step 3: Cross multiply
    279.72x = 419.78 × 171.18
  4. Step 4: Simplify right side
    279.72x = 71,858.37
  5. Step 5: Solve for x
    x = 71,858.37/279.72
  6. Step 6: Final answer
    x = 256.89

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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.