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Finding the Fourth Proportional to 818.92, 1,228.67 and 380.38

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Solution

The fourth proportional to 818.92, 1,228.67 and 380.38 is: 570.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    818.92 : 1,228.67 = 380.38 : x
  2. Step 2: Convert to fraction form
    818.92/1,228.67 = 380.38/x
  3. Step 3: Cross multiply
    818.92x = 1,228.67 × 380.38
  4. Step 4: Simplify right side
    818.92x = 467,361.49
  5. Step 5: Solve for x
    x = 467,361.49/818.92
  6. Step 6: Final answer
    x = 570.70

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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.