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Finding the Fourth Proportional to 287.40, 430.38 and 271.56

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Solution

The fourth proportional to 287.40, 430.38 and 271.56 is: 406.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.40 : 430.38 = 271.56 : x
  2. Step 2: Convert to fraction form
    287.40/430.38 = 271.56/x
  3. Step 3: Cross multiply
    287.40x = 430.38 × 271.56
  4. Step 4: Simplify right side
    287.40x = 116,873.99
  5. Step 5: Solve for x
    x = 116,873.99/287.40
  6. Step 6: Final answer
    x = 406.66

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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.