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Finding the Fourth Proportional to 640.15, 959.66 and 379.51

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Solution

The fourth proportional to 640.15, 959.66 and 379.51 is: 568.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.15 : 959.66 = 379.51 : x
  2. Step 2: Convert to fraction form
    640.15/959.66 = 379.51/x
  3. Step 3: Cross multiply
    640.15x = 959.66 × 379.51
  4. Step 4: Simplify right side
    640.15x = 364,200.57
  5. Step 5: Solve for x
    x = 364,200.57/640.15
  6. Step 6: Final answer
    x = 568.93

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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.