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Finding the Fourth Proportional to 659.70, 910.11 and 438.78

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Solution

The fourth proportional to 659.70, 910.11 and 438.78 is: 605.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.70 : 910.11 = 438.78 : x
  2. Step 2: Convert to fraction form
    659.70/910.11 = 438.78/x
  3. Step 3: Cross multiply
    659.70x = 910.11 × 438.78
  4. Step 4: Simplify right side
    659.70x = 399,338.07
  5. Step 5: Solve for x
    x = 399,338.07/659.70
  6. Step 6: Final answer
    x = 605.33

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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.