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Finding the Fourth Proportional to 890.65, 1,228.67 and 628.09

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Solution

The fourth proportional to 890.65, 1,228.67 and 628.09 is: 866.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    890.65 : 1,228.67 = 628.09 : x
  2. Step 2: Convert to fraction form
    890.65/1,228.67 = 628.09/x
  3. Step 3: Cross multiply
    890.65x = 1,228.67 × 628.09
  4. Step 4: Simplify right side
    890.65x = 771,712.20
  5. Step 5: Solve for x
    x = 771,712.20/890.65
  6. Step 6: Final answer
    x = 866.46

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.