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Finding the Fourth Proportional to 663.64, 995.99 and 389.96

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Solution

The fourth proportional to 663.64, 995.99 and 389.96 is: 585.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.64 : 995.99 = 389.96 : x
  2. Step 2: Convert to fraction form
    663.64/995.99 = 389.96/x
  3. Step 3: Cross multiply
    663.64x = 995.99 × 389.96
  4. Step 4: Simplify right side
    663.64x = 388,392.80
  5. Step 5: Solve for x
    x = 388,392.80/663.64
  6. Step 6: Final answer
    x = 585.25

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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.