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Finding the Fourth Proportional to 633.90, 950.21 and 428.49

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Solution

The fourth proportional to 633.90, 950.21 and 428.49 is: 642.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    633.90 : 950.21 = 428.49 : x
  2. Step 2: Convert to fraction form
    633.90/950.21 = 428.49/x
  3. Step 3: Cross multiply
    633.90x = 950.21 × 428.49
  4. Step 4: Simplify right side
    633.90x = 407,158.91
  5. Step 5: Solve for x
    x = 407,158.91/633.90
  6. Step 6: Final answer
    x = 642.30

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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.