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Finding the Fourth Proportional to 395.09, 545.21 and 218.05

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Solution

The fourth proportional to 395.09, 545.21 and 218.05 is: 300.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    395.09 : 545.21 = 218.05 : x
  2. Step 2: Convert to fraction form
    395.09/545.21 = 218.05/x
  3. Step 3: Cross multiply
    395.09x = 545.21 × 218.05
  4. Step 4: Simplify right side
    395.09x = 118,883.04
  5. Step 5: Solve for x
    x = 118,883.04/395.09
  6. Step 6: Final answer
    x = 300.90

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.