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Finding the Fourth Proportional to 660.25, 989.65 and 415.59

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Solution

The fourth proportional to 660.25, 989.65 and 415.59 is: 622.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.25 : 989.65 = 415.59 : x
  2. Step 2: Convert to fraction form
    660.25/989.65 = 415.59/x
  3. Step 3: Cross multiply
    660.25x = 989.65 × 415.59
  4. Step 4: Simplify right side
    660.25x = 411,288.64
  5. Step 5: Solve for x
    x = 411,288.64/660.25
  6. Step 6: Final answer
    x = 622.93

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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.