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Finding the Fourth Proportional to 420.42, 630.66 and 418.02

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Solution

The fourth proportional to 420.42, 630.66 and 418.02 is: 627.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.42 : 630.66 = 418.02 : x
  2. Step 2: Convert to fraction form
    420.42/630.66 = 418.02/x
  3. Step 3: Cross multiply
    420.42x = 630.66 × 418.02
  4. Step 4: Simplify right side
    420.42x = 263,628.49
  5. Step 5: Solve for x
    x = 263,628.49/420.42
  6. Step 6: Final answer
    x = 627.06

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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.