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Finding the Fourth Proportional to 663.40, 995.84 and 420.06

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Solution

The fourth proportional to 663.40, 995.84 and 420.06 is: 630.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    663.40 : 995.84 = 420.06 : x
  2. Step 2: Convert to fraction form
    663.40/995.84 = 420.06/x
  3. Step 3: Cross multiply
    663.40x = 995.84 × 420.06
  4. Step 4: Simplify right side
    663.40x = 418,312.55
  5. Step 5: Solve for x
    x = 418,312.55/663.40
  6. Step 6: Final answer
    x = 630.56

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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.