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Finding the Fourth Proportional to 649.21, 896.40 and 428.47

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Solution

The fourth proportional to 649.21, 896.40 and 428.47 is: 591.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    649.21 : 896.40 = 428.47 : x
  2. Step 2: Convert to fraction form
    649.21/896.40 = 428.47/x
  3. Step 3: Cross multiply
    649.21x = 896.40 × 428.47
  4. Step 4: Simplify right side
    649.21x = 384,080.51
  5. Step 5: Solve for x
    x = 384,080.51/649.21
  6. Step 6: Final answer
    x = 591.61

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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.