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Finding the Fourth Proportional to 638.70, 880.71 and 491.01

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Solution

The fourth proportional to 638.70, 880.71 and 491.01 is: 677.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    638.70 : 880.71 = 491.01 : x
  2. Step 2: Convert to fraction form
    638.70/880.71 = 491.01/x
  3. Step 3: Cross multiply
    638.70x = 880.71 × 491.01
  4. Step 4: Simplify right side
    638.70x = 432,437.42
  5. Step 5: Solve for x
    x = 432,437.42/638.70
  6. Step 6: Final answer
    x = 677.06

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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.