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Finding the Fourth Proportional to 638.93, 882.02 and 491.51

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Solution

The fourth proportional to 638.93, 882.02 and 491.51 is: 678.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.93 : 882.02 = 491.51 : x
  2. Step 2: Convert to fraction form
    638.93/882.02 = 491.51/x
  3. Step 3: Cross multiply
    638.93x = 882.02 × 491.51
  4. Step 4: Simplify right side
    638.93x = 433,521.65
  5. Step 5: Solve for x
    x = 433,521.65/638.93
  6. Step 6: Final answer
    x = 678.51

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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.