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Finding the Fourth Proportional to 608.09, 838.60 and 398.45

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Solution

The fourth proportional to 608.09, 838.60 and 398.45 is: 549.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    608.09 : 838.60 = 398.45 : x
  2. Step 2: Convert to fraction form
    608.09/838.60 = 398.45/x
  3. Step 3: Cross multiply
    608.09x = 838.60 × 398.45
  4. Step 4: Simplify right side
    608.09x = 334,139.22
  5. Step 5: Solve for x
    x = 334,139.22/608.09
  6. Step 6: Final answer
    x = 549.49

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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.