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Finding the Fourth Proportional to 451.81, 678.18 and 287.47

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Solution

The fourth proportional to 451.81, 678.18 and 287.47 is: 431.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    451.81 : 678.18 = 287.47 : x
  2. Step 2: Convert to fraction form
    451.81/678.18 = 287.47/x
  3. Step 3: Cross multiply
    451.81x = 678.18 × 287.47
  4. Step 4: Simplify right side
    451.81x = 194,953.01
  5. Step 5: Solve for x
    x = 194,953.01/451.81
  6. Step 6: Final answer
    x = 431.50

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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.