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Finding the Fourth Proportional to 660.21, 990.68 and 371.67

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Solution

The fourth proportional to 660.21, 990.68 and 371.67 is: 557.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.21 : 990.68 = 371.67 : x
  2. Step 2: Convert to fraction form
    660.21/990.68 = 371.67/x
  3. Step 3: Cross multiply
    660.21x = 990.68 × 371.67
  4. Step 4: Simplify right side
    660.21x = 368,204.18
  5. Step 5: Solve for x
    x = 368,204.18/660.21
  6. Step 6: Final answer
    x = 557.71

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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.