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Finding the Fourth Proportional to 485.21, 727.66 and 279.88

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Solution

The fourth proportional to 485.21, 727.66 and 279.88 is: 419.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.21 : 727.66 = 279.88 : x
  2. Step 2: Convert to fraction form
    485.21/727.66 = 279.88/x
  3. Step 3: Cross multiply
    485.21x = 727.66 × 279.88
  4. Step 4: Simplify right side
    485.21x = 203,656.01
  5. Step 5: Solve for x
    x = 203,656.01/485.21
  6. Step 6: Final answer
    x = 419.73

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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.