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Finding the Fourth Proportional to 654.12, 902.64 and 421.20

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Solution

The fourth proportional to 654.12, 902.64 and 421.20 is: 581.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.12 : 902.64 = 421.20 : x
  2. Step 2: Convert to fraction form
    654.12/902.64 = 421.20/x
  3. Step 3: Cross multiply
    654.12x = 902.64 × 421.20
  4. Step 4: Simplify right side
    654.12x = 380,191.97
  5. Step 5: Solve for x
    x = 380,191.97/654.12
  6. Step 6: Final answer
    x = 581.23

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.