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Finding the Fourth Proportional to 628.67, 871.23 and 619.86

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Solution

The fourth proportional to 628.67, 871.23 and 619.86 is: 859.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.67 : 871.23 = 619.86 : x
  2. Step 2: Convert to fraction form
    628.67/871.23 = 619.86/x
  3. Step 3: Cross multiply
    628.67x = 871.23 × 619.86
  4. Step 4: Simplify right side
    628.67x = 540,040.63
  5. Step 5: Solve for x
    x = 540,040.63/628.67
  6. Step 6: Final answer
    x = 859.02

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.