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Finding the Fourth Proportional to 420.75, 631.45 and 288.66

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Solution

The fourth proportional to 420.75, 631.45 and 288.66 is: 433.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.75 : 631.45 = 288.66 : x
  2. Step 2: Convert to fraction form
    420.75/631.45 = 288.66/x
  3. Step 3: Cross multiply
    420.75x = 631.45 × 288.66
  4. Step 4: Simplify right side
    420.75x = 182,276.00
  5. Step 5: Solve for x
    x = 182,276.00/420.75
  6. Step 6: Final answer
    x = 433.22

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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.