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Finding the Fourth Proportional to 660.98, 990.51 and 478.76

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Solution

The fourth proportional to 660.98, 990.51 and 478.76 is: 717.44

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.98 : 990.51 = 478.76 : x
  2. Step 2: Convert to fraction form
    660.98/990.51 = 478.76/x
  3. Step 3: Cross multiply
    660.98x = 990.51 × 478.76
  4. Step 4: Simplify right side
    660.98x = 474,216.57
  5. Step 5: Solve for x
    x = 474,216.57/660.98
  6. Step 6: Final answer
    x = 717.44

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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.