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Finding the Fourth Proportional to 765.75, 1,147.71 and 278.54

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Solution

The fourth proportional to 765.75, 1,147.71 and 278.54 is: 417.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    765.75 : 1,147.71 = 278.54 : x
  2. Step 2: Convert to fraction form
    765.75/1,147.71 = 278.54/x
  3. Step 3: Cross multiply
    765.75x = 1,147.71 × 278.54
  4. Step 4: Simplify right side
    765.75x = 319,677.40
  5. Step 5: Solve for x
    x = 319,677.40/765.75
  6. Step 6: Final answer
    x = 417.47

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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.