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Finding the Fourth Proportional to 660.16, 990.29 and 386.29

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Solution

The fourth proportional to 660.16, 990.29 and 386.29 is: 579.46

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.16 : 990.29 = 386.29 : x
  2. Step 2: Convert to fraction form
    660.16/990.29 = 386.29/x
  3. Step 3: Cross multiply
    660.16x = 990.29 × 386.29
  4. Step 4: Simplify right side
    660.16x = 382,539.12
  5. Step 5: Solve for x
    x = 382,539.12/660.16
  6. Step 6: Final answer
    x = 579.46

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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.