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Finding the Fourth Proportional to 681.79, 940.86 and 398.26

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Solution

The fourth proportional to 681.79, 940.86 and 398.26 is: 549.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.79 : 940.86 = 398.26 : x
  2. Step 2: Convert to fraction form
    681.79/940.86 = 398.26/x
  3. Step 3: Cross multiply
    681.79x = 940.86 × 398.26
  4. Step 4: Simplify right side
    681.79x = 374,706.90
  5. Step 5: Solve for x
    x = 374,706.90/681.79
  6. Step 6: Final answer
    x = 549.59

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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.