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Finding the Fourth Proportional to 309.21, 465.87 and 279.96

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Solution

The fourth proportional to 309.21, 465.87 and 279.96 is: 421.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    309.21 : 465.87 = 279.96 : x
  2. Step 2: Convert to fraction form
    309.21/465.87 = 279.96/x
  3. Step 3: Cross multiply
    309.21x = 465.87 × 279.96
  4. Step 4: Simplify right side
    309.21x = 130,424.97
  5. Step 5: Solve for x
    x = 130,424.97/309.21
  6. Step 6: Final answer
    x = 421.80

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.