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Finding the Fourth Proportional to 681.42, 939.84 and 419.22

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Solution

The fourth proportional to 681.42, 939.84 and 419.22 is: 578.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.42 : 939.84 = 419.22 : x
  2. Step 2: Convert to fraction form
    681.42/939.84 = 419.22/x
  3. Step 3: Cross multiply
    681.42x = 939.84 × 419.22
  4. Step 4: Simplify right side
    681.42x = 393,999.72
  5. Step 5: Solve for x
    x = 393,999.72/681.42
  6. Step 6: Final answer
    x = 578.20

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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.