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Finding the Fourth Proportional to 640.78, 883.40 and 547.12

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Solution

The fourth proportional to 640.78, 883.40 and 547.12 is: 754.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.78 : 883.40 = 547.12 : x
  2. Step 2: Convert to fraction form
    640.78/883.40 = 547.12/x
  3. Step 3: Cross multiply
    640.78x = 883.40 × 547.12
  4. Step 4: Simplify right side
    640.78x = 483,325.81
  5. Step 5: Solve for x
    x = 483,325.81/640.78
  6. Step 6: Final answer
    x = 754.28

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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.