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Finding the Fourth Proportional to 660.37, 911.34 and 398.38

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Solution

The fourth proportional to 660.37, 911.34 and 398.38 is: 549.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.37 : 911.34 = 398.38 : x
  2. Step 2: Convert to fraction form
    660.37/911.34 = 398.38/x
  3. Step 3: Cross multiply
    660.37x = 911.34 × 398.38
  4. Step 4: Simplify right side
    660.37x = 363,053.08
  5. Step 5: Solve for x
    x = 363,053.08/660.37
  6. Step 6: Final answer
    x = 549.78

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1.5x scale

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.