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Finding the Fourth Proportional to 871.81, 1,307.74 and 213.69

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Solution

The fourth proportional to 871.81, 1,307.74 and 213.69 is: 320.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    871.81 : 1,307.74 = 213.69 : x
  2. Step 2: Convert to fraction form
    871.81/1,307.74 = 213.69/x
  3. Step 3: Cross multiply
    871.81x = 1,307.74 × 213.69
  4. Step 4: Simplify right side
    871.81x = 279,455.73
  5. Step 5: Solve for x
    x = 279,455.73/871.81
  6. Step 6: Final answer
    x = 320.55

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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.