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Finding the Fourth Proportional to 279.65, 419.78 and 171.72

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Solution

The fourth proportional to 279.65, 419.78 and 171.72 is: 257.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.65 : 419.78 = 171.72 : x
  2. Step 2: Convert to fraction form
    279.65/419.78 = 171.72/x
  3. Step 3: Cross multiply
    279.65x = 419.78 × 171.72
  4. Step 4: Simplify right side
    279.65x = 72,085.05
  5. Step 5: Solve for x
    x = 72,085.05/279.65
  6. Step 6: Final answer
    x = 257.77

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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.