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Finding the Fourth Proportional to 434.70, 650.70 and 421.20

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Solution

The fourth proportional to 434.70, 650.70 and 421.20 is: 630.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    434.70 : 650.70 = 421.20 : x
  2. Step 2: Convert to fraction form
    434.70/650.70 = 421.20/x
  3. Step 3: Cross multiply
    434.70x = 650.70 × 421.20
  4. Step 4: Simplify right side
    434.70x = 274,074.84
  5. Step 5: Solve for x
    x = 274,074.84/434.70
  6. Step 6: Final answer
    x = 630.49

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1.5x scale

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.