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Finding the Fourth Proportional to 430.15, 645.29 and 156.21

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Solution

The fourth proportional to 430.15, 645.29 and 156.21 is: 234.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.15 : 645.29 = 156.21 : x
  2. Step 2: Convert to fraction form
    430.15/645.29 = 156.21/x
  3. Step 3: Cross multiply
    430.15x = 645.29 × 156.21
  4. Step 4: Simplify right side
    430.15x = 100,799.97
  5. Step 5: Solve for x
    x = 100,799.97/430.15
  6. Step 6: Final answer
    x = 234.34

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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.