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Finding the Fourth Proportional to 686.79, 945.86 and 651.58

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Solution

The fourth proportional to 686.79, 945.86 and 651.58 is: 897.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.79 : 945.86 = 651.58 : x
  2. Step 2: Convert to fraction form
    686.79/945.86 = 651.58/x
  3. Step 3: Cross multiply
    686.79x = 945.86 × 651.58
  4. Step 4: Simplify right side
    686.79x = 616,297.84
  5. Step 5: Solve for x
    x = 616,297.84/686.79
  6. Step 6: Final answer
    x = 897.36

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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.