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Finding the Fourth Proportional to 435.60, 654.30 and 420.30

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Solution

The fourth proportional to 435.60, 654.30 and 420.30 is: 631.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    435.60 : 654.30 = 420.30 : x
  2. Step 2: Convert to fraction form
    435.60/654.30 = 420.30/x
  3. Step 3: Cross multiply
    435.60x = 654.30 × 420.30
  4. Step 4: Simplify right side
    435.60x = 275,002.29
  5. Step 5: Solve for x
    x = 275,002.29/435.60
  6. Step 6: Final answer
    x = 631.32

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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.