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Finding the Fourth Proportional to 660.80, 911.76 and 427.84

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Solution

The fourth proportional to 660.80, 911.76 and 427.84 is: 590.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.80 : 911.76 = 427.84 : x
  2. Step 2: Convert to fraction form
    660.80/911.76 = 427.84/x
  3. Step 3: Cross multiply
    660.80x = 911.76 × 427.84
  4. Step 4: Simplify right side
    660.80x = 390,087.40
  5. Step 5: Solve for x
    x = 390,087.40/660.80
  6. Step 6: Final answer
    x = 590.33

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.