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Finding the Fourth Proportional to 438.96, 657.78 and 428.22

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Solution

The fourth proportional to 438.96, 657.78 and 428.22 is: 641.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.96 : 657.78 = 428.22 : x
  2. Step 2: Convert to fraction form
    438.96/657.78 = 428.22/x
  3. Step 3: Cross multiply
    438.96x = 657.78 × 428.22
  4. Step 4: Simplify right side
    438.96x = 281,674.55
  5. Step 5: Solve for x
    x = 281,674.55/438.96
  6. Step 6: Final answer
    x = 641.69

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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.