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Finding the Fourth Proportional to 649.08, 896.15 and 428.40

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Solution

The fourth proportional to 649.08, 896.15 and 428.40 is: 591.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.08 : 896.15 = 428.40 : x
  2. Step 2: Convert to fraction form
    649.08/896.15 = 428.40/x
  3. Step 3: Cross multiply
    649.08x = 896.15 × 428.40
  4. Step 4: Simplify right side
    649.08x = 383,908.52
  5. Step 5: Solve for x
    x = 383,908.52/649.08
  6. Step 6: Final answer
    x = 591.47

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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.