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Finding the Fourth Proportional to 649.72, 896.58 and 428.78

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Solution

The fourth proportional to 649.72, 896.58 and 428.78 is: 591.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.72 : 896.58 = 428.78 : x
  2. Step 2: Convert to fraction form
    649.72/896.58 = 428.78/x
  3. Step 3: Cross multiply
    649.72x = 896.58 × 428.78
  4. Step 4: Simplify right side
    649.72x = 384,435.57
  5. Step 5: Solve for x
    x = 384,435.57/649.72
  6. Step 6: Final answer
    x = 591.69

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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.