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Finding the Fourth Proportional to 280.19, 420.19 and 171.65

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Solution

The fourth proportional to 280.19, 420.19 and 171.65 is: 257.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.19 : 420.19 = 171.65 : x
  2. Step 2: Convert to fraction form
    280.19/420.19 = 171.65/x
  3. Step 3: Cross multiply
    280.19x = 420.19 × 171.65
  4. Step 4: Simplify right side
    280.19x = 72,126.23
  5. Step 5: Solve for x
    x = 72,126.23/280.19
  6. Step 6: Final answer
    x = 257.42

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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.