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Finding the Fourth Proportional to 430.40, 645.60 and 214.04

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Solution

The fourth proportional to 430.40, 645.60 and 214.04 is: 321.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.40 : 645.60 = 214.04 : x
  2. Step 2: Convert to fraction form
    430.40/645.60 = 214.04/x
  3. Step 3: Cross multiply
    430.40x = 645.60 × 214.04
  4. Step 4: Simplify right side
    430.40x = 138,184.22
  5. Step 5: Solve for x
    x = 138,184.22/430.40
  6. Step 6: Final answer
    x = 321.06

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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.