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Finding the Fourth Proportional to 660.90, 911.34 and 427.98

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Solution

The fourth proportional to 660.90, 911.34 and 427.98 is: 590.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.90 : 911.34 = 427.98 : x
  2. Step 2: Convert to fraction form
    660.90/911.34 = 427.98/x
  3. Step 3: Cross multiply
    660.90x = 911.34 × 427.98
  4. Step 4: Simplify right side
    660.90x = 390,035.29
  5. Step 5: Solve for x
    x = 390,035.29/660.90
  6. Step 6: Final answer
    x = 590.16

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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.