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Finding the Fourth Proportional to 663.60, 989.47 and 662.69

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Solution

The fourth proportional to 663.60, 989.47 and 662.69 is: 988.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.60 : 989.47 = 662.69 : x
  2. Step 2: Convert to fraction form
    663.60/989.47 = 662.69/x
  3. Step 3: Cross multiply
    663.60x = 989.47 × 662.69
  4. Step 4: Simplify right side
    663.60x = 655,715.18
  5. Step 5: Solve for x
    x = 655,715.18/663.60
  6. Step 6: Final answer
    x = 988.11

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.