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Finding the Fourth Proportional to 287.84, 428.99 and 287.39

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Solution

The fourth proportional to 287.84, 428.99 and 287.39 is: 428.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.84 : 428.99 = 287.39 : x
  2. Step 2: Convert to fraction form
    287.84/428.99 = 287.39/x
  3. Step 3: Cross multiply
    287.84x = 428.99 × 287.39
  4. Step 4: Simplify right side
    287.84x = 123,287.44
  5. Step 5: Solve for x
    x = 123,287.44/287.84
  6. Step 6: Final answer
    x = 428.32

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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.