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Finding the Fourth Proportional to 660.34, 990.58 and 221.42

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Solution

The fourth proportional to 660.34, 990.58 and 221.42 is: 332.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.34 : 990.58 = 221.42 : x
  2. Step 2: Convert to fraction form
    660.34/990.58 = 221.42/x
  3. Step 3: Cross multiply
    660.34x = 990.58 × 221.42
  4. Step 4: Simplify right side
    660.34x = 219,334.22
  5. Step 5: Solve for x
    x = 219,334.22/660.34
  6. Step 6: Final answer
    x = 332.15

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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.