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Finding the Fourth Proportional to 420.89, 630.94 and 266.36

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Solution

The fourth proportional to 420.89, 630.94 and 266.36 is: 399.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.89 : 630.94 = 266.36 : x
  2. Step 2: Convert to fraction form
    420.89/630.94 = 266.36/x
  3. Step 3: Cross multiply
    420.89x = 630.94 × 266.36
  4. Step 4: Simplify right side
    420.89x = 168,058.09
  5. Step 5: Solve for x
    x = 168,058.09/420.89
  6. Step 6: Final answer
    x = 399.30

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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.