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Finding the Fourth Proportional to 423.28, 634.84 and 287.20

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Solution

The fourth proportional to 423.28, 634.84 and 287.20 is: 430.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    423.28 : 634.84 = 287.20 : x
  2. Step 2: Convert to fraction form
    423.28/634.84 = 287.20/x
  3. Step 3: Cross multiply
    423.28x = 634.84 × 287.20
  4. Step 4: Simplify right side
    423.28x = 182,322.55
  5. Step 5: Solve for x
    x = 182,322.55/423.28
  6. Step 6: Final answer
    x = 430.74

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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.