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Finding the Fourth Proportional to 285.41, 393.99 and 219.80

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Solution

The fourth proportional to 285.41, 393.99 and 219.80 is: 303.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.41 : 393.99 = 219.80 : x
  2. Step 2: Convert to fraction form
    285.41/393.99 = 219.80/x
  3. Step 3: Cross multiply
    285.41x = 393.99 × 219.80
  4. Step 4: Simplify right side
    285.41x = 86,597.56
  5. Step 5: Solve for x
    x = 86,597.56/285.41
  6. Step 6: Final answer
    x = 303.42

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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.