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Finding the Fourth Proportional to 427.13, 640.69 and 170.81

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Solution

The fourth proportional to 427.13, 640.69 and 170.81 is: 256.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.13 : 640.69 = 170.81 : x
  2. Step 2: Convert to fraction form
    427.13/640.69 = 170.81/x
  3. Step 3: Cross multiply
    427.13x = 640.69 × 170.81
  4. Step 4: Simplify right side
    427.13x = 109,432.63
  5. Step 5: Solve for x
    x = 109,432.63/427.13
  6. Step 6: Final answer
    x = 256.21

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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.