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Finding the Fourth Proportional to 890.66, 1,335.33 and 428.08

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Solution

The fourth proportional to 890.66, 1,335.33 and 428.08 is: 641.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    890.66 : 1,335.33 = 428.08 : x
  2. Step 2: Convert to fraction form
    890.66/1,335.33 = 428.08/x
  3. Step 3: Cross multiply
    890.66x = 1,335.33 × 428.08
  4. Step 4: Simplify right side
    890.66x = 571,624.73
  5. Step 5: Solve for x
    x = 571,624.73/890.66
  6. Step 6: Final answer
    x = 641.80

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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.