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Finding the Fourth Proportional to 430.05, 645.29 and 210.81

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Solution

The fourth proportional to 430.05, 645.29 and 210.81 is: 316.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.05 : 645.29 = 210.81 : x
  2. Step 2: Convert to fraction form
    430.05/645.29 = 210.81/x
  3. Step 3: Cross multiply
    430.05x = 645.29 × 210.81
  4. Step 4: Simplify right side
    430.05x = 136,032.53
  5. Step 5: Solve for x
    x = 136,032.53/430.05
  6. Step 6: Final answer
    x = 316.32

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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.