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Finding the Fourth Proportional to 430.70, 645.75 and 307.31

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Solution

The fourth proportional to 430.70, 645.75 and 307.31 is: 460.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.70 : 645.75 = 307.31 : x
  2. Step 2: Convert to fraction form
    430.70/645.75 = 307.31/x
  3. Step 3: Cross multiply
    430.70x = 645.75 × 307.31
  4. Step 4: Simplify right side
    430.70x = 198,445.43
  5. Step 5: Solve for x
    x = 198,445.43/430.70
  6. Step 6: Final answer
    x = 460.75

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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.