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Finding the Fourth Proportional to 430.58, 647.07 and 420.17

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Solution

The fourth proportional to 430.58, 647.07 and 420.17 is: 631.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    430.58 : 647.07 = 420.17 : x
  2. Step 2: Convert to fraction form
    430.58/647.07 = 420.17/x
  3. Step 3: Cross multiply
    430.58x = 647.07 × 420.17
  4. Step 4: Simplify right side
    430.58x = 271,876.17
  5. Step 5: Solve for x
    x = 271,876.17/430.58
  6. Step 6: Final answer
    x = 631.43

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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.