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Finding the Fourth Proportional to 387.06, 580.86 and 213.66

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Solution

The fourth proportional to 387.06, 580.86 and 213.66 is: 320.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.06 : 580.86 = 213.66 : x
  2. Step 2: Convert to fraction form
    387.06/580.86 = 213.66/x
  3. Step 3: Cross multiply
    387.06x = 580.86 × 213.66
  4. Step 4: Simplify right side
    387.06x = 124,106.55
  5. Step 5: Solve for x
    x = 124,106.55/387.06
  6. Step 6: Final answer
    x = 320.64

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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.