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Finding the Fourth Proportional to 486.99, 729.72 and 212.79

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Solution

The fourth proportional to 486.99, 729.72 and 212.79 is: 318.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.99 : 729.72 = 212.79 : x
  2. Step 2: Convert to fraction form
    486.99/729.72 = 212.79/x
  3. Step 3: Cross multiply
    486.99x = 729.72 × 212.79
  4. Step 4: Simplify right side
    486.99x = 155,277.12
  5. Step 5: Solve for x
    x = 155,277.12/486.99
  6. Step 6: Final answer
    x = 318.85

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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.