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Finding the Fourth Proportional to 485.14, 728.05 and 211.09

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Solution

The fourth proportional to 485.14, 728.05 and 211.09 is: 316.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    485.14 : 728.05 = 211.09 : x
  2. Step 2: Convert to fraction form
    485.14/728.05 = 211.09/x
  3. Step 3: Cross multiply
    485.14x = 728.05 × 211.09
  4. Step 4: Simplify right side
    485.14x = 153,684.07
  5. Step 5: Solve for x
    x = 153,684.07/485.14
  6. Step 6: Final answer
    x = 316.78

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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.