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Finding the Fourth Proportional to 639.08, 957.47 and 388.46

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Solution

The fourth proportional to 639.08, 957.47 and 388.46 is: 581.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    639.08 : 957.47 = 388.46 : x
  2. Step 2: Convert to fraction form
    639.08/957.47 = 388.46/x
  3. Step 3: Cross multiply
    639.08x = 957.47 × 388.46
  4. Step 4: Simplify right side
    639.08x = 371,934.98
  5. Step 5: Solve for x
    x = 371,934.98/639.08
  6. Step 6: Final answer
    x = 581.99

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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.