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Finding the Fourth Proportional to 647.49, 894 and 398.89

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Solution

The fourth proportional to 647.49, 894 and 398.89 is: 550.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    647.49 : 894 = 398.89 : x
  2. Step 2: Convert to fraction form
    647.49/894 = 398.89/x
  3. Step 3: Cross multiply
    647.49x = 894 × 398.89
  4. Step 4: Simplify right side
    647.49x = 356,607.66
  5. Step 5: Solve for x
    x = 356,607.66/647.49
  6. Step 6: Final answer
    x = 550.75

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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.