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Finding the Fourth Proportional to 612.86, 919.28 and 305.09

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Solution

The fourth proportional to 612.86, 919.28 and 305.09 is: 457.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    612.86 : 919.28 = 305.09 : x
  2. Step 2: Convert to fraction form
    612.86/919.28 = 305.09/x
  3. Step 3: Cross multiply
    612.86x = 919.28 × 305.09
  4. Step 4: Simplify right side
    612.86x = 280,462.75
  5. Step 5: Solve for x
    x = 280,462.75/612.86
  6. Step 6: Final answer
    x = 457.63

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Double scale
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Similar ratio
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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.