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Finding the Fourth Proportional to 664.41, 995.70 and 420.50

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Solution

The fourth proportional to 664.41, 995.70 and 420.50 is: 630.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    664.41 : 995.70 = 420.50 : x
  2. Step 2: Convert to fraction form
    664.41/995.70 = 420.50/x
  3. Step 3: Cross multiply
    664.41x = 995.70 × 420.50
  4. Step 4: Simplify right side
    664.41x = 418,689.36
  5. Step 5: Solve for x
    x = 418,689.36/664.41
  6. Step 6: Final answer
    x = 630.17

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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.