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Finding the Fourth Proportional to 645.74, 970.20 and 414.72

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Solution

The fourth proportional to 645.74, 970.20 and 414.72 is: 623.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.74 : 970.20 = 414.72 : x
  2. Step 2: Convert to fraction form
    645.74/970.20 = 414.72/x
  3. Step 3: Cross multiply
    645.74x = 970.20 × 414.72
  4. Step 4: Simplify right side
    645.74x = 402,361.34
  5. Step 5: Solve for x
    x = 402,361.34/645.74
  6. Step 6: Final answer
    x = 623.10

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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.