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Finding the Fourth Proportional to 640.71, 959.51 and 380.30

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Solution

The fourth proportional to 640.71, 959.51 and 380.30 is: 569.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    640.71 : 959.51 = 380.30 : x
  2. Step 2: Convert to fraction form
    640.71/959.51 = 380.30/x
  3. Step 3: Cross multiply
    640.71x = 959.51 × 380.30
  4. Step 4: Simplify right side
    640.71x = 364,897.81
  5. Step 5: Solve for x
    x = 364,897.81/640.71
  6. Step 6: Final answer
    x = 569.52

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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.