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Finding the Fourth Proportional to 659.79, 989.91 and 415.98

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Solution

The fourth proportional to 659.79, 989.91 and 415.98 is: 624.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    659.79 : 989.91 = 415.98 : x
  2. Step 2: Convert to fraction form
    659.79/989.91 = 415.98/x
  3. Step 3: Cross multiply
    659.79x = 989.91 × 415.98
  4. Step 4: Simplify right side
    659.79x = 411,782.76
  5. Step 5: Solve for x
    x = 411,782.76/659.79
  6. Step 6: Final answer
    x = 624.11

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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.