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Finding the Fourth Proportional to 427.66, 645.34 and 412.40

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Solution

The fourth proportional to 427.66, 645.34 and 412.40 is: 622.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    427.66 : 645.34 = 412.40 : x
  2. Step 2: Convert to fraction form
    427.66/645.34 = 412.40/x
  3. Step 3: Cross multiply
    427.66x = 645.34 × 412.40
  4. Step 4: Simplify right side
    427.66x = 266,138.22
  5. Step 5: Solve for x
    x = 266,138.22/427.66
  6. Step 6: Final answer
    x = 622.31

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.