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Finding the Fourth Proportional to 306.48, 456.78 and 285.72

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Solution

The fourth proportional to 306.48, 456.78 and 285.72 is: 425.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    306.48 : 456.78 = 285.72 : x
  2. Step 2: Convert to fraction form
    306.48/456.78 = 285.72/x
  3. Step 3: Cross multiply
    306.48x = 456.78 × 285.72
  4. Step 4: Simplify right side
    306.48x = 130,511.18
  5. Step 5: Solve for x
    x = 130,511.18/306.48
  6. Step 6: Final answer
    x = 425.84

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.