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Finding the Fourth Proportional to 641.21, 960.77 and 421.37

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Solution

The fourth proportional to 641.21, 960.77 and 421.37 is: 631.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.21 : 960.77 = 421.37 : x
  2. Step 2: Convert to fraction form
    641.21/960.77 = 421.37/x
  3. Step 3: Cross multiply
    641.21x = 960.77 × 421.37
  4. Step 4: Simplify right side
    641.21x = 404,839.51
  5. Step 5: Solve for x
    x = 404,839.51/641.21
  6. Step 6: Final answer
    x = 631.37

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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.