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Finding the Fourth Proportional to 286.80, 427.02 and 285.20

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Solution

The fourth proportional to 286.80, 427.02 and 285.20 is: 424.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    286.80 : 427.02 = 285.20 : x
  2. Step 2: Convert to fraction form
    286.80/427.02 = 285.20/x
  3. Step 3: Cross multiply
    286.80x = 427.02 × 285.20
  4. Step 4: Simplify right side
    286.80x = 121,786.10
  5. Step 5: Solve for x
    x = 121,786.10/286.80
  6. Step 6: Final answer
    x = 424.64

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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.