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Finding the Fourth Proportional to 660.53, 990.34 and 478.28

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Solution

The fourth proportional to 660.53, 990.34 and 478.28 is: 717.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.53 : 990.34 = 478.28 : x
  2. Step 2: Convert to fraction form
    660.53/990.34 = 478.28/x
  3. Step 3: Cross multiply
    660.53x = 990.34 × 478.28
  4. Step 4: Simplify right side
    660.53x = 473,659.82
  5. Step 5: Solve for x
    x = 473,659.82/660.53
  6. Step 6: Final answer
    x = 717.09

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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.