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Finding the Fourth Proportional to 686.07, 945.84 and 664.55

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Solution

The fourth proportional to 686.07, 945.84 and 664.55 is: 916.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.07 : 945.84 = 664.55 : x
  2. Step 2: Convert to fraction form
    686.07/945.84 = 664.55/x
  3. Step 3: Cross multiply
    686.07x = 945.84 × 664.55
  4. Step 4: Simplify right side
    686.07x = 628,564.60
  5. Step 5: Solve for x
    x = 628,564.60/686.07
  6. Step 6: Final answer
    x = 916.18

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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.