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Finding the Fourth Proportional to 660.33, 990.14 and 386.51

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Solution

The fourth proportional to 660.33, 990.14 and 386.51 is: 579.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.33 : 990.14 = 386.51 : x
  2. Step 2: Convert to fraction form
    660.33/990.14 = 386.51/x
  3. Step 3: Cross multiply
    660.33x = 990.14 × 386.51
  4. Step 4: Simplify right side
    660.33x = 382,692.13
  5. Step 5: Solve for x
    x = 382,692.13/660.33
  6. Step 6: Final answer
    x = 579.55

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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.