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Finding the Fourth Proportional to 660.14, 989.88 and 386.30

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Solution

The fourth proportional to 660.14, 989.88 and 386.30 is: 579.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.14 : 989.88 = 386.30 : x
  2. Step 2: Convert to fraction form
    660.14/989.88 = 386.30/x
  3. Step 3: Cross multiply
    660.14x = 989.88 × 386.30
  4. Step 4: Simplify right side
    660.14x = 382,385.69
  5. Step 5: Solve for x
    x = 382,385.69/660.14
  6. Step 6: Final answer
    x = 579.25

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.