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Finding the Fourth Proportional to 660.18, 911.10 and 398.16

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Solution

The fourth proportional to 660.18, 911.10 and 398.16 is: 549.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.18 : 911.10 = 398.16 : x
  2. Step 2: Convert to fraction form
    660.18/911.10 = 398.16/x
  3. Step 3: Cross multiply
    660.18x = 911.10 × 398.16
  4. Step 4: Simplify right side
    660.18x = 362,763.58
  5. Step 5: Solve for x
    x = 362,763.58/660.18
  6. Step 6: Final answer
    x = 549.49

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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.