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Finding the Fourth Proportional to 656.78, 978.41 and 637.65

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Solution

The fourth proportional to 656.78, 978.41 and 637.65 is: 949.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    656.78 : 978.41 = 637.65 : x
  2. Step 2: Convert to fraction form
    656.78/978.41 = 637.65/x
  3. Step 3: Cross multiply
    656.78x = 978.41 × 637.65
  4. Step 4: Simplify right side
    656.78x = 623,884.73
  5. Step 5: Solve for x
    x = 623,884.73/656.78
  6. Step 6: Final answer
    x = 949.92

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.