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Finding the Fourth Proportional to 285.79, 394.39 and 154.80

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Solution

The fourth proportional to 285.79, 394.39 and 154.80 is: 213.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.79 : 394.39 = 154.80 : x
  2. Step 2: Convert to fraction form
    285.79/394.39 = 154.80/x
  3. Step 3: Cross multiply
    285.79x = 394.39 × 154.80
  4. Step 4: Simplify right side
    285.79x = 61,051.57
  5. Step 5: Solve for x
    x = 61,051.57/285.79
  6. Step 6: Final answer
    x = 213.62

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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.