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Finding the Fourth Proportional to 420.90, 631.34 and 132.35

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Solution

The fourth proportional to 420.90, 631.34 and 132.35 is: 198.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.90 : 631.34 = 132.35 : x
  2. Step 2: Convert to fraction form
    420.90/631.34 = 132.35/x
  3. Step 3: Cross multiply
    420.90x = 631.34 × 132.35
  4. Step 4: Simplify right side
    420.90x = 83,554.03
  5. Step 5: Solve for x
    x = 83,554.03/420.90
  6. Step 6: Final answer
    x = 198.51

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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.