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Finding the Fourth Proportional to 427.40, 639.58 and 265.16

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Solution

The fourth proportional to 427.40, 639.58 and 265.16 is: 396.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.40 : 639.58 = 265.16 : x
  2. Step 2: Convert to fraction form
    427.40/639.58 = 265.16/x
  3. Step 3: Cross multiply
    427.40x = 639.58 × 265.16
  4. Step 4: Simplify right side
    427.40x = 169,591.03
  5. Step 5: Solve for x
    x = 169,591.03/427.40
  6. Step 6: Final answer
    x = 396.80

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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.