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Finding the Fourth Proportional to 665.06, 995.55 and 420.84

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Solution

The fourth proportional to 665.06, 995.55 and 420.84 is: 629.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    665.06 : 995.55 = 420.84 : x
  2. Step 2: Convert to fraction form
    665.06/995.55 = 420.84/x
  3. Step 3: Cross multiply
    665.06x = 995.55 × 420.84
  4. Step 4: Simplify right side
    665.06x = 418,967.26
  5. Step 5: Solve for x
    x = 418,967.26/665.06
  6. Step 6: Final answer
    x = 629.97

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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.