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Finding the Fourth Proportional to 420.77, 631.12 and 132.20

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Solution

The fourth proportional to 420.77, 631.12 and 132.20 is: 198.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.77 : 631.12 = 132.20 : x
  2. Step 2: Convert to fraction form
    420.77/631.12 = 132.20/x
  3. Step 3: Cross multiply
    420.77x = 631.12 × 132.20
  4. Step 4: Simplify right side
    420.77x = 83,430.25
  5. Step 5: Solve for x
    x = 83,430.25/420.77
  6. Step 6: Final answer
    x = 198.28

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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.