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Finding the Fourth Proportional to 305.70, 458.55 and 285.30

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Solution

The fourth proportional to 305.70, 458.55 and 285.30 is: 427.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.70 : 458.55 = 285.30 : x
  2. Step 2: Convert to fraction form
    305.70/458.55 = 285.30/x
  3. Step 3: Cross multiply
    305.70x = 458.55 × 285.30
  4. Step 4: Simplify right side
    305.70x = 130,824.32
  5. Step 5: Solve for x
    x = 130,824.32/305.70
  6. Step 6: Final answer
    x = 427.95

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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.