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Finding the Fourth Proportional to 639.87, 883.10 and 374.40

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Solution

The fourth proportional to 639.87, 883.10 and 374.40 is: 516.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.87 : 883.10 = 374.40 : x
  2. Step 2: Convert to fraction form
    639.87/883.10 = 374.40/x
  3. Step 3: Cross multiply
    639.87x = 883.10 × 374.40
  4. Step 4: Simplify right side
    639.87x = 330,632.64
  5. Step 5: Solve for x
    x = 330,632.64/639.87
  6. Step 6: Final answer
    x = 516.72

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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.