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Finding the Fourth Proportional to 663.85, 995.78 and 339.45

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Solution

The fourth proportional to 663.85, 995.78 and 339.45 is: 509.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.85 : 995.78 = 339.45 : x
  2. Step 2: Convert to fraction form
    663.85/995.78 = 339.45/x
  3. Step 3: Cross multiply
    663.85x = 995.78 × 339.45
  4. Step 4: Simplify right side
    663.85x = 338,017.52
  5. Step 5: Solve for x
    x = 338,017.52/663.85
  6. Step 6: Final answer
    x = 509.18

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Similar ratio
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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.