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Finding the Fourth Proportional to 287.07, 430.38 and 142.71

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Solution

The fourth proportional to 287.07, 430.38 and 142.71 is: 213.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.07 : 430.38 = 142.71 : x
  2. Step 2: Convert to fraction form
    287.07/430.38 = 142.71/x
  3. Step 3: Cross multiply
    287.07x = 430.38 × 142.71
  4. Step 4: Simplify right side
    287.07x = 61,419.53
  5. Step 5: Solve for x
    x = 61,419.53/287.07
  6. Step 6: Final answer
    x = 213.95

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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.