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Finding the Fourth Proportional to 690.75, 953.27 and 428.71

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Solution

The fourth proportional to 690.75, 953.27 and 428.71 is: 591.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    690.75 : 953.27 = 428.71 : x
  2. Step 2: Convert to fraction form
    690.75/953.27 = 428.71/x
  3. Step 3: Cross multiply
    690.75x = 953.27 × 428.71
  4. Step 4: Simplify right side
    690.75x = 408,676.38
  5. Step 5: Solve for x
    x = 408,676.38/690.75
  6. Step 6: Final answer
    x = 591.64

Related Problems

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Half scale
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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.