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Finding the Fourth Proportional to 871.09, 1,306.02 and 438.01

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Solution

The fourth proportional to 871.09, 1,306.02 and 438.01 is: 656.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    871.09 : 1,306.02 = 438.01 : x
  2. Step 2: Convert to fraction form
    871.09/1,306.02 = 438.01/x
  3. Step 3: Cross multiply
    871.09x = 1,306.02 × 438.01
  4. Step 4: Simplify right side
    871.09x = 572,049.82
  5. Step 5: Solve for x
    x = 572,049.82/871.09
  6. Step 6: Final answer
    x = 656.71

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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.