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Finding the Fourth Proportional to 639.98, 882.60 and 419.12

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Solution

The fourth proportional to 639.98, 882.60 and 419.12 is: 578.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.98 : 882.60 = 419.12 : x
  2. Step 2: Convert to fraction form
    639.98/882.60 = 419.12/x
  3. Step 3: Cross multiply
    639.98x = 882.60 × 419.12
  4. Step 4: Simplify right side
    639.98x = 369,915.31
  5. Step 5: Solve for x
    x = 369,915.31/639.98
  6. Step 6: Final answer
    x = 578.01

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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.