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Finding the Fourth Proportional to 386.46, 579.16 and 212.87

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Solution

The fourth proportional to 386.46, 579.16 and 212.87 is: 319.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    386.46 : 579.16 = 212.87 : x
  2. Step 2: Convert to fraction form
    386.46/579.16 = 212.87/x
  3. Step 3: Cross multiply
    386.46x = 579.16 × 212.87
  4. Step 4: Simplify right side
    386.46x = 123,282.89
  5. Step 5: Solve for x
    x = 123,282.89/386.46
  6. Step 6: Final answer
    x = 319.01

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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.