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Finding the Fourth Proportional to 420.21, 626.04 and 409.16

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Solution

The fourth proportional to 420.21, 626.04 and 409.16 is: 609.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    420.21 : 626.04 = 409.16 : x
  2. Step 2: Convert to fraction form
    420.21/626.04 = 409.16/x
  3. Step 3: Cross multiply
    420.21x = 626.04 × 409.16
  4. Step 4: Simplify right side
    420.21x = 256,147.40
  5. Step 5: Solve for x
    x = 256,147.40/420.21
  6. Step 6: Final answer
    x = 609.57

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.