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Finding the Fourth Proportional to 656.97, 985.80 and 425.80

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Solution

The fourth proportional to 656.97, 985.80 and 425.80 is: 638.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    656.97 : 985.80 = 425.80 : x
  2. Step 2: Convert to fraction form
    656.97/985.80 = 425.80/x
  3. Step 3: Cross multiply
    656.97x = 985.80 × 425.80
  4. Step 4: Simplify right side
    656.97x = 419,751.18
  5. Step 5: Solve for x
    x = 419,751.18/656.97
  6. Step 6: Final answer
    x = 638.92

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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.