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Finding the Fourth Proportional to 428.85, 645.54 and 366.21

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Solution

The fourth proportional to 428.85, 645.54 and 366.21 is: 551.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    428.85 : 645.54 = 366.21 : x
  2. Step 2: Convert to fraction form
    428.85/645.54 = 366.21/x
  3. Step 3: Cross multiply
    428.85x = 645.54 × 366.21
  4. Step 4: Simplify right side
    428.85x = 236,403.20
  5. Step 5: Solve for x
    x = 236,403.20/428.85
  6. Step 6: Final answer
    x = 551.25

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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.