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Finding the Fourth Proportional to 639.29, 957.83 and 407.84

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Solution

The fourth proportional to 639.29, 957.83 and 407.84 is: 611.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.29 : 957.83 = 407.84 : x
  2. Step 2: Convert to fraction form
    639.29/957.83 = 407.84/x
  3. Step 3: Cross multiply
    639.29x = 957.83 × 407.84
  4. Step 4: Simplify right side
    639.29x = 390,634.56
  5. Step 5: Solve for x
    x = 390,634.56/639.29
  6. Step 6: Final answer
    x = 611.04

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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.