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Finding the Fourth Proportional to 421.84, 633.21 and 345.70

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Solution

The fourth proportional to 421.84, 633.21 and 345.70 is: 518.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.84 : 633.21 = 345.70 : x
  2. Step 2: Convert to fraction form
    421.84/633.21 = 345.70/x
  3. Step 3: Cross multiply
    421.84x = 633.21 × 345.70
  4. Step 4: Simplify right side
    421.84x = 218,900.70
  5. Step 5: Solve for x
    x = 218,900.70/421.84
  6. Step 6: Final answer
    x = 518.92

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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.