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Finding the Fourth Proportional to 660.71, 989.79 and 512.58

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Solution

The fourth proportional to 660.71, 989.79 and 512.58 is: 767.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.71 : 989.79 = 512.58 : x
  2. Step 2: Convert to fraction form
    660.71/989.79 = 512.58/x
  3. Step 3: Cross multiply
    660.71x = 989.79 × 512.58
  4. Step 4: Simplify right side
    660.71x = 507,343.86
  5. Step 5: Solve for x
    x = 507,343.86/660.71
  6. Step 6: Final answer
    x = 767.87

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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.