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Finding the Fourth Proportional to 660.11, 989.75 and 386.06

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Solution

The fourth proportional to 660.11, 989.75 and 386.06 is: 578.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.11 : 989.75 = 386.06 : x
  2. Step 2: Convert to fraction form
    660.11/989.75 = 386.06/x
  3. Step 3: Cross multiply
    660.11x = 989.75 × 386.06
  4. Step 4: Simplify right side
    660.11x = 382,096.01
  5. Step 5: Solve for x
    x = 382,096.01/660.11
  6. Step 6: Final answer
    x = 578.84

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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.