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Finding the Fourth Proportional to 656.77, 985.08 and 412.55

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Solution

The fourth proportional to 656.77, 985.08 and 412.55 is: 618.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    656.77 : 985.08 = 412.55 : x
  2. Step 2: Convert to fraction form
    656.77/985.08 = 412.55/x
  3. Step 3: Cross multiply
    656.77x = 985.08 × 412.55
  4. Step 4: Simplify right side
    656.77x = 406,394.75
  5. Step 5: Solve for x
    x = 406,394.75/656.77
  6. Step 6: Final answer
    x = 618.78

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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.