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Finding the Fourth Proportional to 681.21, 939.98 and 415.53

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Solution

The fourth proportional to 681.21, 939.98 and 415.53 is: 573.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.21 : 939.98 = 415.53 : x
  2. Step 2: Convert to fraction form
    681.21/939.98 = 415.53/x
  3. Step 3: Cross multiply
    681.21x = 939.98 × 415.53
  4. Step 4: Simplify right side
    681.21x = 390,590.93
  5. Step 5: Solve for x
    x = 390,590.93/681.21
  6. Step 6: Final answer
    x = 573.38

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1.5x scale

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.