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Finding the Fourth Proportional to 663.80, 994.80 and 386.30

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Solution

The fourth proportional to 663.80, 994.80 and 386.30 is: 578.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.80 : 994.80 = 386.30 : x
  2. Step 2: Convert to fraction form
    663.80/994.80 = 386.30/x
  3. Step 3: Cross multiply
    663.80x = 994.80 × 386.30
  4. Step 4: Simplify right side
    663.80x = 384,291.24
  5. Step 5: Solve for x
    x = 384,291.24/663.80
  6. Step 6: Final answer
    x = 578.93

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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.