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Finding the Fourth Proportional to 660.20, 989.85 and 313.47

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Solution

The fourth proportional to 660.20, 989.85 and 313.47 is: 469.99

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.20 : 989.85 = 313.47 : x
  2. Step 2: Convert to fraction form
    660.20/989.85 = 313.47/x
  3. Step 3: Cross multiply
    660.20x = 989.85 × 313.47
  4. Step 4: Simplify right side
    660.20x = 310,286.81
  5. Step 5: Solve for x
    x = 310,286.81/660.20
  6. Step 6: Final answer
    x = 469.99

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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.