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Finding the Fourth Proportional to 608.12, 838.91 and 398.21

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Solution

The fourth proportional to 608.12, 838.91 and 398.21 is: 549.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    608.12 : 838.91 = 398.21 : x
  2. Step 2: Convert to fraction form
    608.12/838.91 = 398.21/x
  3. Step 3: Cross multiply
    608.12x = 838.91 × 398.21
  4. Step 4: Simplify right side
    608.12x = 334,062.35
  5. Step 5: Solve for x
    x = 334,062.35/608.12
  6. Step 6: Final answer
    x = 549.34

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.