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Finding the Fourth Proportional to 660.14, 990.21 and 371.42

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Solution

The fourth proportional to 660.14, 990.21 and 371.42 is: 557.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.14 : 990.21 = 371.42 : x
  2. Step 2: Convert to fraction form
    660.14/990.21 = 371.42/x
  3. Step 3: Cross multiply
    660.14x = 990.21 × 371.42
  4. Step 4: Simplify right side
    660.14x = 367,783.80
  5. Step 5: Solve for x
    x = 367,783.80/660.14
  6. Step 6: Final answer
    x = 557.13

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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.