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Finding the Fourth Proportional to 639.05, 958.94 and 419.94

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Solution

The fourth proportional to 639.05, 958.94 and 419.94 is: 630.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.05 : 958.94 = 419.94 : x
  2. Step 2: Convert to fraction form
    639.05/958.94 = 419.94/x
  3. Step 3: Cross multiply
    639.05x = 958.94 × 419.94
  4. Step 4: Simplify right side
    639.05x = 402,695.16
  5. Step 5: Solve for x
    x = 402,695.16/639.05
  6. Step 6: Final answer
    x = 630.15

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.