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Finding the Fourth Proportional to 287.34, 428.25 and 286.89

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Solution

The fourth proportional to 287.34, 428.25 and 286.89 is: 427.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.34 : 428.25 = 286.89 : x
  2. Step 2: Convert to fraction form
    287.34/428.25 = 286.89/x
  3. Step 3: Cross multiply
    287.34x = 428.25 × 286.89
  4. Step 4: Simplify right side
    287.34x = 122,858.50
  5. Step 5: Solve for x
    x = 122,858.50/287.34
  6. Step 6: Final answer
    x = 427.57

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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.