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Finding the Fourth Proportional to 817.09, 1,126.46 and 639.34

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Solution

The fourth proportional to 817.09, 1,126.46 and 639.34 is: 881.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    817.09 : 1,126.46 = 639.34 : x
  2. Step 2: Convert to fraction form
    817.09/1,126.46 = 639.34/x
  3. Step 3: Cross multiply
    817.09x = 1,126.46 × 639.34
  4. Step 4: Simplify right side
    817.09x = 720,189.72
  5. Step 5: Solve for x
    x = 720,189.72/817.09
  6. Step 6: Final answer
    x = 881.41

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Double scale
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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.