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Finding the Fourth Proportional to 920.85, 1,381.27 and 459.19

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Solution

The fourth proportional to 920.85, 1,381.27 and 459.19 is: 688.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    920.85 : 1,381.27 = 459.19 : x
  2. Step 2: Convert to fraction form
    920.85/1,381.27 = 459.19/x
  3. Step 3: Cross multiply
    920.85x = 1,381.27 × 459.19
  4. Step 4: Simplify right side
    920.85x = 634,265.37
  5. Step 5: Solve for x
    x = 634,265.37/920.85
  6. Step 6: Final answer
    x = 688.78

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.