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Finding the Fourth Proportional to 639.24, 957.84 and 395.40

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Solution

The fourth proportional to 639.24, 957.84 and 395.40 is: 592.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.24 : 957.84 = 395.40 : x
  2. Step 2: Convert to fraction form
    639.24/957.84 = 395.40/x
  3. Step 3: Cross multiply
    639.24x = 957.84 × 395.40
  4. Step 4: Simplify right side
    639.24x = 378,729.94
  5. Step 5: Solve for x
    x = 378,729.94/639.24
  6. Step 6: Final answer
    x = 592.47

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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.