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Finding the Fourth Proportional to 681.30, 940.10 and 419.28

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Solution

The fourth proportional to 681.30, 940.10 and 419.28 is: 578.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.30 : 940.10 = 419.28 : x
  2. Step 2: Convert to fraction form
    681.30/940.10 = 419.28/x
  3. Step 3: Cross multiply
    681.30x = 940.10 × 419.28
  4. Step 4: Simplify right side
    681.30x = 394,165.13
  5. Step 5: Solve for x
    x = 394,165.13/681.30
  6. Step 6: Final answer
    x = 578.55

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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.