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Finding the Fourth Proportional to 287.78, 429.21 and 277.45

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Solution

The fourth proportional to 287.78, 429.21 and 277.45 is: 413.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.78 : 429.21 = 277.45 : x
  2. Step 2: Convert to fraction form
    287.78/429.21 = 277.45/x
  3. Step 3: Cross multiply
    287.78x = 429.21 × 277.45
  4. Step 4: Simplify right side
    287.78x = 119,083.24
  5. Step 5: Solve for x
    x = 119,083.24/287.78
  6. Step 6: Final answer
    x = 413.81

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.