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Finding the Fourth Proportional to 640.11, 957.78 and 380.22

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Solution

The fourth proportional to 640.11, 957.78 and 380.22 is: 568.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.11 : 957.78 = 380.22 : x
  2. Step 2: Convert to fraction form
    640.11/957.78 = 380.22/x
  3. Step 3: Cross multiply
    640.11x = 957.78 × 380.22
  4. Step 4: Simplify right side
    640.11x = 364,167.11
  5. Step 5: Solve for x
    x = 364,167.11/640.11
  6. Step 6: Final answer
    x = 568.91

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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.