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Finding the Fourth Proportional to 279.08, 419 and 257.60

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Solution

The fourth proportional to 279.08, 419 and 257.60 is: 386.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    279.08 : 419 = 257.60 : x
  2. Step 2: Convert to fraction form
    279.08/419 = 257.60/x
  3. Step 3: Cross multiply
    279.08x = 419 × 257.60
  4. Step 4: Simplify right side
    279.08x = 107,934.40
  5. Step 5: Solve for x
    x = 107,934.40/279.08
  6. Step 6: Final answer
    x = 386.75

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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.