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Finding the Fourth Proportional to 660.29, 910.80 and 398.25

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Solution

The fourth proportional to 660.29, 910.80 and 398.25 is: 549.35

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.29 : 910.80 = 398.25 : x
  2. Step 2: Convert to fraction form
    660.29/910.80 = 398.25/x
  3. Step 3: Cross multiply
    660.29x = 910.80 × 398.25
  4. Step 4: Simplify right side
    660.29x = 362,726.10
  5. Step 5: Solve for x
    x = 362,726.10/660.29
  6. Step 6: Final answer
    x = 549.35

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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.