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Finding the Fourth Proportional to 681.70, 940.85 and 419.90

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Solution

The fourth proportional to 681.70, 940.85 and 419.90 is: 579.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.70 : 940.85 = 419.90 : x
  2. Step 2: Convert to fraction form
    681.70/940.85 = 419.90/x
  3. Step 3: Cross multiply
    681.70x = 940.85 × 419.90
  4. Step 4: Simplify right side
    681.70x = 395,062.92
  5. Step 5: Solve for x
    x = 395,062.92/681.70
  6. Step 6: Final answer
    x = 579.53

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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.