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Finding the Fourth Proportional to 686.76, 945.36 and 520.68

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Solution

The fourth proportional to 686.76, 945.36 and 520.68 is: 716.74

Step by Step Solution

  1. Step 1: Write the proportion equation
    686.76 : 945.36 = 520.68 : x
  2. Step 2: Convert to fraction form
    686.76/945.36 = 520.68/x
  3. Step 3: Cross multiply
    686.76x = 945.36 × 520.68
  4. Step 4: Simplify right side
    686.76x = 492,230.04
  5. Step 5: Solve for x
    x = 492,230.04/686.76
  6. Step 6: Final answer
    x = 716.74

Related Problems

Find fourth proportional to 343.38, 472.68 and 260.34
Half scale
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Double scale
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Similar ratio
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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.