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Finding the Fourth Proportional to 279.84, 420.16 and 171.30

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Solution

The fourth proportional to 279.84, 420.16 and 171.30 is: 257.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.84 : 420.16 = 171.30 : x
  2. Step 2: Convert to fraction form
    279.84/420.16 = 171.30/x
  3. Step 3: Cross multiply
    279.84x = 420.16 × 171.30
  4. Step 4: Simplify right side
    279.84x = 71,973.41
  5. Step 5: Solve for x
    x = 71,973.41/279.84
  6. Step 6: Final answer
    x = 257.19

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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.