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Finding the Fourth Proportional to 649.88, 896.64 and 428.78

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Solution

The fourth proportional to 649.88, 896.64 and 428.78 is: 591.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.88 : 896.64 = 428.78 : x
  2. Step 2: Convert to fraction form
    649.88/896.64 = 428.78/x
  3. Step 3: Cross multiply
    649.88x = 896.64 × 428.78
  4. Step 4: Simplify right side
    649.88x = 384,461.30
  5. Step 5: Solve for x
    x = 384,461.30/649.88
  6. Step 6: Final answer
    x = 591.59

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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.