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Finding the Fourth Proportional to 287.37, 428.88 and 259.69

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Solution

The fourth proportional to 287.37, 428.88 and 259.69 is: 387.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.37 : 428.88 = 259.69 : x
  2. Step 2: Convert to fraction form
    287.37/428.88 = 259.69/x
  3. Step 3: Cross multiply
    287.37x = 428.88 × 259.69
  4. Step 4: Simplify right side
    287.37x = 111,375.85
  5. Step 5: Solve for x
    x = 111,375.85/287.37
  6. Step 6: Final answer
    x = 387.57

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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.