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Finding the Fourth Proportional to 660.68, 911.40 and 427.76

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Solution

The fourth proportional to 660.68, 911.40 and 427.76 is: 590.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.68 : 911.40 = 427.76 : x
  2. Step 2: Convert to fraction form
    660.68/911.40 = 427.76/x
  3. Step 3: Cross multiply
    660.68x = 911.40 × 427.76
  4. Step 4: Simplify right side
    660.68x = 389,860.46
  5. Step 5: Solve for x
    x = 389,860.46/660.68
  6. Step 6: Final answer
    x = 590.09

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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.