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Finding the Fourth Proportional to 657.21, 985.71 and 427.73

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Solution

The fourth proportional to 657.21, 985.71 and 427.73 is: 641.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    657.21 : 985.71 = 427.73 : x
  2. Step 2: Convert to fraction form
    657.21/985.71 = 427.73/x
  3. Step 3: Cross multiply
    657.21x = 985.71 × 427.73
  4. Step 4: Simplify right side
    657.21x = 421,617.74
  5. Step 5: Solve for x
    x = 421,617.74/657.21
  6. Step 6: Final answer
    x = 641.53

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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.