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Finding the Fourth Proportional to 660.30, 910.71 and 398.04

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Solution

The fourth proportional to 660.30, 910.71 and 398.04 is: 548.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.30 : 910.71 = 398.04 : x
  2. Step 2: Convert to fraction form
    660.30/910.71 = 398.04/x
  3. Step 3: Cross multiply
    660.30x = 910.71 × 398.04
  4. Step 4: Simplify right side
    660.30x = 362,499.01
  5. Step 5: Solve for x
    x = 362,499.01/660.30
  6. Step 6: Final answer
    x = 548.99

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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.