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Finding the Fourth Proportional to 305.66, 458.90 and 280.19

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Solution

The fourth proportional to 305.66, 458.90 and 280.19 is: 420.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    305.66 : 458.90 = 280.19 : x
  2. Step 2: Convert to fraction form
    305.66/458.90 = 280.19/x
  3. Step 3: Cross multiply
    305.66x = 458.90 × 280.19
  4. Step 4: Simplify right side
    305.66x = 128,575.50
  5. Step 5: Solve for x
    x = 128,575.50/305.66
  6. Step 6: Final answer
    x = 420.66

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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.