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Finding the Fourth Proportional to 426.06, 639.70 and 279.35

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Solution

The fourth proportional to 426.06, 639.70 and 279.35 is: 419.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    426.06 : 639.70 = 279.35 : x
  2. Step 2: Convert to fraction form
    426.06/639.70 = 279.35/x
  3. Step 3: Cross multiply
    426.06x = 639.70 × 279.35
  4. Step 4: Simplify right side
    426.06x = 178,698.70
  5. Step 5: Solve for x
    x = 178,698.70/426.06
  6. Step 6: Final answer
    x = 419.42

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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.