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Finding the Fourth Proportional to 639.98, 882.50 and 499.84

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Solution

The fourth proportional to 639.98, 882.50 and 499.84 is: 689.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.98 : 882.50 = 499.84 : x
  2. Step 2: Convert to fraction form
    639.98/882.50 = 499.84/x
  3. Step 3: Cross multiply
    639.98x = 882.50 × 499.84
  4. Step 4: Simplify right side
    639.98x = 441,108.80
  5. Step 5: Solve for x
    x = 441,108.80/639.98
  6. Step 6: Final answer
    x = 689.25

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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.