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Finding the Fourth Proportional to 780.57, 1,171.28 and 347.71

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Solution

The fourth proportional to 780.57, 1,171.28 and 347.71 is: 521.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.57 : 1,171.28 = 347.71 : x
  2. Step 2: Convert to fraction form
    780.57/1,171.28 = 347.71/x
  3. Step 3: Cross multiply
    780.57x = 1,171.28 × 347.71
  4. Step 4: Simplify right side
    780.57x = 407,265.77
  5. Step 5: Solve for x
    x = 407,265.77/780.57
  6. Step 6: Final answer
    x = 521.75

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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.