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Finding the Fourth Proportional to 430.41, 645.60 and 105.78

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Solution

The fourth proportional to 430.41, 645.60 and 105.78 is: 158.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.41 : 645.60 = 105.78 : x
  2. Step 2: Convert to fraction form
    430.41/645.60 = 105.78/x
  3. Step 3: Cross multiply
    430.41x = 645.60 × 105.78
  4. Step 4: Simplify right side
    430.41x = 68,291.57
  5. Step 5: Solve for x
    x = 68,291.57/430.41
  6. Step 6: Final answer
    x = 158.67

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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.