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Finding the Fourth Proportional to 660.37, 989.45 and 399.58

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Solution

The fourth proportional to 660.37, 989.45 and 399.58 is: 598.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.37 : 989.45 = 399.58 : x
  2. Step 2: Convert to fraction form
    660.37/989.45 = 399.58/x
  3. Step 3: Cross multiply
    660.37x = 989.45 × 399.58
  4. Step 4: Simplify right side
    660.37x = 395,364.43
  5. Step 5: Solve for x
    x = 395,364.43/660.37
  6. Step 6: Final answer
    x = 598.70

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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.