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Finding the Fourth Proportional to 654.40, 981.28 and 380.57

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Solution

The fourth proportional to 654.40, 981.28 and 380.57 is: 570.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    654.40 : 981.28 = 380.57 : x
  2. Step 2: Convert to fraction form
    654.40/981.28 = 380.57/x
  3. Step 3: Cross multiply
    654.40x = 981.28 × 380.57
  4. Step 4: Simplify right side
    654.40x = 373,445.73
  5. Step 5: Solve for x
    x = 373,445.73/654.40
  6. Step 6: Final answer
    x = 570.67

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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.