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Finding the Fourth Proportional to 661.64, 913.24 and 428.76

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Solution

The fourth proportional to 661.64, 913.24 and 428.76 is: 591.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.64 : 913.24 = 428.76 : x
  2. Step 2: Convert to fraction form
    661.64/913.24 = 428.76/x
  3. Step 3: Cross multiply
    661.64x = 913.24 × 428.76
  4. Step 4: Simplify right side
    661.64x = 391,560.78
  5. Step 5: Solve for x
    x = 391,560.78/661.64
  6. Step 6: Final answer
    x = 591.80

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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.