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Finding the Fourth Proportional to 287.83, 431.74 and 82.40

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Solution

The fourth proportional to 287.83, 431.74 and 82.40 is: 123.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.83 : 431.74 = 82.40 : x
  2. Step 2: Convert to fraction form
    287.83/431.74 = 82.40/x
  3. Step 3: Cross multiply
    287.83x = 431.74 × 82.40
  4. Step 4: Simplify right side
    287.83x = 35,575.38
  5. Step 5: Solve for x
    x = 35,575.38/287.83
  6. Step 6: Final answer
    x = 123.60

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.