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Finding the Fourth Proportional to 287.19, 428.31 and 283.59

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Solution

The fourth proportional to 287.19, 428.31 and 283.59 is: 422.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.19 : 428.31 = 283.59 : x
  2. Step 2: Convert to fraction form
    287.19/428.31 = 283.59/x
  3. Step 3: Cross multiply
    287.19x = 428.31 × 283.59
  4. Step 4: Simplify right side
    287.19x = 121,464.43
  5. Step 5: Solve for x
    x = 121,464.43/287.19
  6. Step 6: Final answer
    x = 422.94

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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.