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Finding the Fourth Proportional to 639.79, 883.78 and 501.65

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Solution

The fourth proportional to 639.79, 883.78 and 501.65 is: 692.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.79 : 883.78 = 501.65 : x
  2. Step 2: Convert to fraction form
    639.79/883.78 = 501.65/x
  3. Step 3: Cross multiply
    639.79x = 883.78 × 501.65
  4. Step 4: Simplify right side
    639.79x = 443,348.24
  5. Step 5: Solve for x
    x = 443,348.24/639.79
  6. Step 6: Final answer
    x = 692.96

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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.