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Finding the Fourth Proportional to 430.89, 645.81 and 199.45

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Solution

The fourth proportional to 430.89, 645.81 and 199.45 is: 298.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.89 : 645.81 = 199.45 : x
  2. Step 2: Convert to fraction form
    430.89/645.81 = 199.45/x
  3. Step 3: Cross multiply
    430.89x = 645.81 × 199.45
  4. Step 4: Simplify right side
    430.89x = 128,806.80
  5. Step 5: Solve for x
    x = 128,806.80/430.89
  6. Step 6: Final answer
    x = 298.93

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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.