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Finding the Fourth Proportional to 285.93, 428.49 and 208.71

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Solution

The fourth proportional to 285.93, 428.49 and 208.71 is: 312.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    285.93 : 428.49 = 208.71 : x
  2. Step 2: Convert to fraction form
    285.93/428.49 = 208.71/x
  3. Step 3: Cross multiply
    285.93x = 428.49 × 208.71
  4. Step 4: Simplify right side
    285.93x = 89,430.15
  5. Step 5: Solve for x
    x = 89,430.15/285.93
  6. Step 6: Final answer
    x = 312.77

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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.