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Finding the Fourth Proportional to 641.42, 885.23 and 420.50

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Solution

The fourth proportional to 641.42, 885.23 and 420.50 is: 580.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    641.42 : 885.23 = 420.50 : x
  2. Step 2: Convert to fraction form
    641.42/885.23 = 420.50/x
  3. Step 3: Cross multiply
    641.42x = 885.23 × 420.50
  4. Step 4: Simplify right side
    641.42x = 372,232.69
  5. Step 5: Solve for x
    x = 372,232.69/641.42
  6. Step 6: Final answer
    x = 580.33

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.